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A right angle at the centre is a quarter of the whole · 12 practice problems

6.SP.B.46.RP.A.3

Generated variants — 12

Freshly produced from the archetype’s parameters — problem, figure, and solution derived together.

Variant 1 easy answer: 7 students

The circle graph at the right shows the favorite snacks of the $20$ students in Jia's class. How many students like pizza?

Show solution

1 · Understandwhat's really being asked

20 students are split between four snacks. Chicken has 25 percent and Other 15 percent; the tteokbokki slice is a right angle and pizza is unlabelled. We want how many like pizza.

Givens

There are 20 students in the class.
Chicken is 25 percent and Other is 15 percent.
The tteokbokki slice has a right angle at the centre.

Unknowns

How many students like pizza.

Constraints

The four slices together are the whole class.

2 · Planchoose the strategy

#1 Draw a Diagram · also uses: #8 Analyze the Units#16 Count the Complement

Two of the four slices are labelled and a third is marked with a right angle, which is a percentage written in a different language. Translate it, then get the fourth slice as what is left of 100.

3 · Execute3 carry out the plan

1Read the right angle as a share

#1 Draw a Diagram 6.SP.B.4

A full turn round the centre is 360 degrees, and a right angle is 90 of them -- a quarter of the circle.

90 \div 360 = 0.25 = 25\%

Tteokbokki is 25 percent.

2Take the three known slices off 100

#16 Count the Complement 6.RP.A.3

The four slices make the whole class, so the rest is pizza.

100 - 25 - 15 - 25 = 35

Pizza is 35 percent.

3Turn the percent into students

#8 Analyze the Units 6.RP.A.3

35 percent of the 20 students.

20 \times 0.35 = 7

7 students like pizza.

Answer: 7 students

4 · Reviewdoes it hold up?

The four percentages add to 100, and 7 students is 35 percent of 20 -- both books balance.

Another way: Measuring the pizza slice's angle would give 126 degrees, and dividing that by 360 gives the same share; the right angle is quicker because it needs no protractor.

Standardsmin grade 6

6.SP.B.4 Display numerical data in plots (dot, histogram, box) — Reading a circle graph, including a slice marked by its angle.
6.RP.A.3 Use ratio and rate reasoning to solve problems — Turning the leftover percentage into a number of students.

💡Takeaway. An angle on a circle graph is a percentage in a different language. A right angle always says a quarter.

Variant 2 easy answer: 12 students

The circle graph at the right shows the favorite snacks of the $40$ students in Jia's class. How many students like pizza?

Show solution

1 · Understandwhat's really being asked

40 students are split between four snacks. Chicken has 35 percent and Other 10 percent; the tteokbokki slice is a right angle and pizza is unlabelled. We want how many like pizza.

Givens

There are 40 students in the class.
Chicken is 35 percent and Other is 10 percent.
The tteokbokki slice has a right angle at the centre.

Unknowns

How many students like pizza.

Constraints

The four slices together are the whole class.

2 · Planchoose the strategy

#1 Draw a Diagram · also uses: #8 Analyze the Units#16 Count the Complement

Two of the four slices are labelled and a third is marked with a right angle, which is a percentage written in a different language. Translate it, then get the fourth slice as what is left of 100.

3 · Execute3 carry out the plan

1Read the right angle as a share

#1 Draw a Diagram 6.SP.B.4

A full turn round the centre is 360 degrees, and a right angle is 90 of them -- a quarter of the circle.

90 \div 360 = 0.25 = 25\%

Tteokbokki is 25 percent.

2Take the three known slices off 100

#16 Count the Complement 6.RP.A.3

The four slices make the whole class, so the rest is pizza.

100 - 35 - 10 - 25 = 30

Pizza is 30 percent.

3Turn the percent into students

#8 Analyze the Units 6.RP.A.3

30 percent of the 40 students.

40 \times 0.3 = 12

12 students like pizza.

Answer: 12 students

4 · Reviewdoes it hold up?

The four percentages add to 100, and 12 students is 30 percent of 40 -- both books balance.

Another way: Measuring the pizza slice's angle would give 108 degrees, and dividing that by 360 gives the same share; the right angle is quicker because it needs no protractor.

Standardsmin grade 6

6.SP.B.4 Display numerical data in plots (dot, histogram, box) — Reading a circle graph, including a slice marked by its angle.
6.RP.A.3 Use ratio and rate reasoning to solve problems — Turning the leftover percentage into a number of students.

💡Takeaway. An angle on a circle graph is a percentage in a different language. A right angle always says a quarter.

Variant 3 easy answer: 20 students

The circle graph at the right shows the favorite snacks of the $40$ students in Jia's class. How many students like pizza?

Show solution

1 · Understandwhat's really being asked

40 students are split between four snacks. Chicken has 20 percent and Other 5 percent; the tteokbokki slice is a right angle and pizza is unlabelled. We want how many like pizza.

Givens

There are 40 students in the class.
Chicken is 20 percent and Other is 5 percent.
The tteokbokki slice has a right angle at the centre.

Unknowns

How many students like pizza.

Constraints

The four slices together are the whole class.

2 · Planchoose the strategy

#1 Draw a Diagram · also uses: #8 Analyze the Units#16 Count the Complement

Two of the four slices are labelled and a third is marked with a right angle, which is a percentage written in a different language. Translate it, then get the fourth slice as what is left of 100.

3 · Execute3 carry out the plan

1Read the right angle as a share

#1 Draw a Diagram 6.SP.B.4

A full turn round the centre is 360 degrees, and a right angle is 90 of them -- a quarter of the circle.

90 \div 360 = 0.25 = 25\%

Tteokbokki is 25 percent.

2Take the three known slices off 100

#16 Count the Complement 6.RP.A.3

The four slices make the whole class, so the rest is pizza.

100 - 20 - 5 - 25 = 50

Pizza is 50 percent.

3Turn the percent into students

#8 Analyze the Units 6.RP.A.3

50 percent of the 40 students.

40 \times 0.5 = 20

20 students like pizza.

Answer: 20 students

4 · Reviewdoes it hold up?

The four percentages add to 100, and 20 students is 50 percent of 40 -- both books balance.

Another way: Measuring the pizza slice's angle would give 180 degrees, and dividing that by 360 gives the same share; the right angle is quicker because it needs no protractor.

Standardsmin grade 6

6.SP.B.4 Display numerical data in plots (dot, histogram, box) — Reading a circle graph, including a slice marked by its angle.
6.RP.A.3 Use ratio and rate reasoning to solve problems — Turning the leftover percentage into a number of students.

💡Takeaway. An angle on a circle graph is a percentage in a different language. A right angle always says a quarter.

Variant 4 easy answer: 14 students

The circle graph at the right shows the favorite snacks of the $40$ students in Jia's class. How many students like pizza?

Show solution

1 · Understandwhat's really being asked

40 students are split between four snacks. Chicken has 25 percent and Other 15 percent; the tteokbokki slice is a right angle and pizza is unlabelled. We want how many like pizza.

Givens

There are 40 students in the class.
Chicken is 25 percent and Other is 15 percent.
The tteokbokki slice has a right angle at the centre.

Unknowns

How many students like pizza.

Constraints

The four slices together are the whole class.

2 · Planchoose the strategy

#1 Draw a Diagram · also uses: #8 Analyze the Units#16 Count the Complement

Two of the four slices are labelled and a third is marked with a right angle, which is a percentage written in a different language. Translate it, then get the fourth slice as what is left of 100.

3 · Execute3 carry out the plan

1Read the right angle as a share

#1 Draw a Diagram 6.SP.B.4

A full turn round the centre is 360 degrees, and a right angle is 90 of them -- a quarter of the circle.

90 \div 360 = 0.25 = 25\%

Tteokbokki is 25 percent.

2Take the three known slices off 100

#16 Count the Complement 6.RP.A.3

The four slices make the whole class, so the rest is pizza.

100 - 25 - 15 - 25 = 35

Pizza is 35 percent.

3Turn the percent into students

#8 Analyze the Units 6.RP.A.3

35 percent of the 40 students.

40 \times 0.35 = 14

14 students like pizza.

Answer: 14 students

4 · Reviewdoes it hold up?

The four percentages add to 100, and 14 students is 35 percent of 40 -- both books balance.

Another way: Measuring the pizza slice's angle would give 126 degrees, and dividing that by 360 gives the same share; the right angle is quicker because it needs no protractor.

Standardsmin grade 6

6.SP.B.4 Display numerical data in plots (dot, histogram, box) — Reading a circle graph, including a slice marked by its angle.
6.RP.A.3 Use ratio and rate reasoning to solve problems — Turning the leftover percentage into a number of students.

💡Takeaway. An angle on a circle graph is a percentage in a different language. A right angle always says a quarter.

Variant 5 medium answer: 3 students

The circle graph at the right shows the favorite snacks of the $60$ students in Jia's class. How many students like pizza?

Show solution

1 · Understandwhat's really being asked

60 students are split between four snacks. Chicken has 45 percent and Other 25 percent; the tteokbokki slice is a right angle and pizza is unlabelled. We want how many like pizza.

Givens

There are 60 students in the class.
Chicken is 45 percent and Other is 25 percent.
The tteokbokki slice has a right angle at the centre.

Unknowns

How many students like pizza.

Constraints

The four slices together are the whole class.

2 · Planchoose the strategy

#1 Draw a Diagram · also uses: #8 Analyze the Units#16 Count the Complement

Two of the four slices are labelled and a third is marked with a right angle, which is a percentage written in a different language. Translate it, then get the fourth slice as what is left of 100.

3 · Execute3 carry out the plan

1Read the right angle as a share

#1 Draw a Diagram 6.SP.B.4

A full turn round the centre is 360 degrees, and a right angle is 90 of them -- a quarter of the circle.

90 \div 360 = 0.25 = 25\%

Tteokbokki is 25 percent.

2Take the three known slices off 100

#16 Count the Complement 6.RP.A.3

The four slices make the whole class, so the rest is pizza.

100 - 45 - 25 - 25 = 5

Pizza is 5 percent.

3Turn the percent into students

#8 Analyze the Units 6.RP.A.3

5 percent of the 60 students.

60 \times 0.05 = 3

3 students like pizza.

Answer: 3 students

4 · Reviewdoes it hold up?

The four percentages add to 100, and 3 students is 5 percent of 60 -- both books balance.

Another way: Measuring the pizza slice's angle would give 18 degrees, and dividing that by 360 gives the same share; the right angle is quicker because it needs no protractor.

Standardsmin grade 6

6.SP.B.4 Display numerical data in plots (dot, histogram, box) — Reading a circle graph, including a slice marked by its angle.
6.RP.A.3 Use ratio and rate reasoning to solve problems — Turning the leftover percentage into a number of students.

💡Takeaway. An angle on a circle graph is a percentage in a different language. A right angle always says a quarter.

Variant 6 medium answer: 28 students

The circle graph at the right shows the favorite snacks of the $80$ students in Jia's class. How many students like pizza?

Show solution

1 · Understandwhat's really being asked

80 students are split between four snacks. Chicken has 25 percent and Other 15 percent; the tteokbokki slice is a right angle and pizza is unlabelled. We want how many like pizza.

Givens

There are 80 students in the class.
Chicken is 25 percent and Other is 15 percent.
The tteokbokki slice has a right angle at the centre.

Unknowns

How many students like pizza.

Constraints

The four slices together are the whole class.

2 · Planchoose the strategy

#1 Draw a Diagram · also uses: #8 Analyze the Units#16 Count the Complement

Two of the four slices are labelled and a third is marked with a right angle, which is a percentage written in a different language. Translate it, then get the fourth slice as what is left of 100.

3 · Execute3 carry out the plan

1Read the right angle as a share

#1 Draw a Diagram 6.SP.B.4

A full turn round the centre is 360 degrees, and a right angle is 90 of them -- a quarter of the circle.

90 \div 360 = 0.25 = 25\%

Tteokbokki is 25 percent.

2Take the three known slices off 100

#16 Count the Complement 6.RP.A.3

The four slices make the whole class, so the rest is pizza.

100 - 25 - 15 - 25 = 35

Pizza is 35 percent.

3Turn the percent into students

#8 Analyze the Units 6.RP.A.3

35 percent of the 80 students.

80 \times 0.35 = 28

28 students like pizza.

Answer: 28 students

4 · Reviewdoes it hold up?

The four percentages add to 100, and 28 students is 35 percent of 80 -- both books balance.

Another way: Measuring the pizza slice's angle would give 126 degrees, and dividing that by 360 gives the same share; the right angle is quicker because it needs no protractor.

Standardsmin grade 6

6.SP.B.4 Display numerical data in plots (dot, histogram, box) — Reading a circle graph, including a slice marked by its angle.
6.RP.A.3 Use ratio and rate reasoning to solve problems — Turning the leftover percentage into a number of students.

💡Takeaway. An angle on a circle graph is a percentage in a different language. A right angle always says a quarter.

Variant 7 medium answer: 4 students

The circle graph at the right shows the favorite snacks of the $80$ students in Jia's class. How many students like pizza?

Show solution

1 · Understandwhat's really being asked

80 students are split between four snacks. Chicken has 50 percent and Other 20 percent; the tteokbokki slice is a right angle and pizza is unlabelled. We want how many like pizza.

Givens

There are 80 students in the class.
Chicken is 50 percent and Other is 20 percent.
The tteokbokki slice has a right angle at the centre.

Unknowns

How many students like pizza.

Constraints

The four slices together are the whole class.

2 · Planchoose the strategy

#1 Draw a Diagram · also uses: #8 Analyze the Units#16 Count the Complement

Two of the four slices are labelled and a third is marked with a right angle, which is a percentage written in a different language. Translate it, then get the fourth slice as what is left of 100.

3 · Execute3 carry out the plan

1Read the right angle as a share

#1 Draw a Diagram 6.SP.B.4

A full turn round the centre is 360 degrees, and a right angle is 90 of them -- a quarter of the circle.

90 \div 360 = 0.25 = 25\%

Tteokbokki is 25 percent.

2Take the three known slices off 100

#16 Count the Complement 6.RP.A.3

The four slices make the whole class, so the rest is pizza.

100 - 50 - 20 - 25 = 5

Pizza is 5 percent.

3Turn the percent into students

#8 Analyze the Units 6.RP.A.3

5 percent of the 80 students.

80 \times 0.05 = 4

4 students like pizza.

Answer: 4 students

4 · Reviewdoes it hold up?

The four percentages add to 100, and 4 students is 5 percent of 80 -- both books balance.

Another way: Measuring the pizza slice's angle would give 18 degrees, and dividing that by 360 gives the same share; the right angle is quicker because it needs no protractor.

Standardsmin grade 6

6.SP.B.4 Display numerical data in plots (dot, histogram, box) — Reading a circle graph, including a slice marked by its angle.
6.RP.A.3 Use ratio and rate reasoning to solve problems — Turning the leftover percentage into a number of students.

💡Takeaway. An angle on a circle graph is a percentage in a different language. A right angle always says a quarter.

Variant 8 medium answer: 50 students

The circle graph at the right shows the favorite snacks of the $100$ students in Jia's class. How many students like pizza?

Show solution

1 · Understandwhat's really being asked

100 students are split between four snacks. Chicken has 20 percent and Other 5 percent; the tteokbokki slice is a right angle and pizza is unlabelled. We want how many like pizza.

Givens

There are 100 students in the class.
Chicken is 20 percent and Other is 5 percent.
The tteokbokki slice has a right angle at the centre.

Unknowns

How many students like pizza.

Constraints

The four slices together are the whole class.

2 · Planchoose the strategy

#1 Draw a Diagram · also uses: #8 Analyze the Units#16 Count the Complement

Two of the four slices are labelled and a third is marked with a right angle, which is a percentage written in a different language. Translate it, then get the fourth slice as what is left of 100.

3 · Execute3 carry out the plan

1Read the right angle as a share

#1 Draw a Diagram 6.SP.B.4

A full turn round the centre is 360 degrees, and a right angle is 90 of them -- a quarter of the circle.

90 \div 360 = 0.25 = 25\%

Tteokbokki is 25 percent.

2Take the three known slices off 100

#16 Count the Complement 6.RP.A.3

The four slices make the whole class, so the rest is pizza.

100 - 20 - 5 - 25 = 50

Pizza is 50 percent.

3Turn the percent into students

#8 Analyze the Units 6.RP.A.3

50 percent of the 100 students.

100 \times 0.5 = 50

50 students like pizza.

Answer: 50 students

4 · Reviewdoes it hold up?

The four percentages add to 100, and 50 students is 50 percent of 100 -- both books balance.

Another way: Measuring the pizza slice's angle would give 180 degrees, and dividing that by 360 gives the same share; the right angle is quicker because it needs no protractor.

Standardsmin grade 6

6.SP.B.4 Display numerical data in plots (dot, histogram, box) — Reading a circle graph, including a slice marked by its angle.
6.RP.A.3 Use ratio and rate reasoning to solve problems — Turning the leftover percentage into a number of students.

💡Takeaway. An angle on a circle graph is a percentage in a different language. A right angle always says a quarter.

Variant 9 hard answer: 80 students

The circle graph at the right shows the favorite snacks of the $200$ students in Jia's class. How many students like pizza?

Show solution

1 · Understandwhat's really being asked

200 students are split between four snacks. Chicken has 30 percent and Other 5 percent; the tteokbokki slice is a right angle and pizza is unlabelled. We want how many like pizza.

Givens

There are 200 students in the class.
Chicken is 30 percent and Other is 5 percent.
The tteokbokki slice has a right angle at the centre.

Unknowns

How many students like pizza.

Constraints

The four slices together are the whole class.

2 · Planchoose the strategy

#1 Draw a Diagram · also uses: #8 Analyze the Units#16 Count the Complement

Two of the four slices are labelled and a third is marked with a right angle, which is a percentage written in a different language. Translate it, then get the fourth slice as what is left of 100.

3 · Execute3 carry out the plan

1Read the right angle as a share

#1 Draw a Diagram 6.SP.B.4

A full turn round the centre is 360 degrees, and a right angle is 90 of them -- a quarter of the circle.

90 \div 360 = 0.25 = 25\%

Tteokbokki is 25 percent.

2Take the three known slices off 100

#16 Count the Complement 6.RP.A.3

The four slices make the whole class, so the rest is pizza.

100 - 30 - 5 - 25 = 40

Pizza is 40 percent.

3Turn the percent into students

#8 Analyze the Units 6.RP.A.3

40 percent of the 200 students.

200 \times 0.4 = 80

80 students like pizza.

Answer: 80 students

4 · Reviewdoes it hold up?

The four percentages add to 100, and 80 students is 40 percent of 200 -- both books balance.

Another way: Measuring the pizza slice's angle would give 144 degrees, and dividing that by 360 gives the same share; the right angle is quicker because it needs no protractor.

Standardsmin grade 6

6.SP.B.4 Display numerical data in plots (dot, histogram, box) — Reading a circle graph, including a slice marked by its angle.
6.RP.A.3 Use ratio and rate reasoning to solve problems — Turning the leftover percentage into a number of students.

💡Takeaway. An angle on a circle graph is a percentage in a different language. A right angle always says a quarter.

Variant 10 hard answer: 50 students

The circle graph at the right shows the favorite snacks of the $250$ students in Jia's class. How many students like pizza?

Show solution

1 · Understandwhat's really being asked

250 students are split between four snacks. Chicken has 30 percent and Other 25 percent; the tteokbokki slice is a right angle and pizza is unlabelled. We want how many like pizza.

Givens

There are 250 students in the class.
Chicken is 30 percent and Other is 25 percent.
The tteokbokki slice has a right angle at the centre.

Unknowns

How many students like pizza.

Constraints

The four slices together are the whole class.

2 · Planchoose the strategy

#1 Draw a Diagram · also uses: #8 Analyze the Units#16 Count the Complement

Two of the four slices are labelled and a third is marked with a right angle, which is a percentage written in a different language. Translate it, then get the fourth slice as what is left of 100.

3 · Execute3 carry out the plan

1Read the right angle as a share

#1 Draw a Diagram 6.SP.B.4

A full turn round the centre is 360 degrees, and a right angle is 90 of them -- a quarter of the circle.

90 \div 360 = 0.25 = 25\%

Tteokbokki is 25 percent.

2Take the three known slices off 100

#16 Count the Complement 6.RP.A.3

The four slices make the whole class, so the rest is pizza.

100 - 30 - 25 - 25 = 20

Pizza is 20 percent.

3Turn the percent into students

#8 Analyze the Units 6.RP.A.3

20 percent of the 250 students.

250 \times 0.2 = 50

50 students like pizza.

Answer: 50 students

4 · Reviewdoes it hold up?

The four percentages add to 100, and 50 students is 20 percent of 250 -- both books balance.

Another way: Measuring the pizza slice's angle would give 72 degrees, and dividing that by 360 gives the same share; the right angle is quicker because it needs no protractor.

Standardsmin grade 6

6.SP.B.4 Display numerical data in plots (dot, histogram, box) — Reading a circle graph, including a slice marked by its angle.
6.RP.A.3 Use ratio and rate reasoning to solve problems — Turning the leftover percentage into a number of students.

💡Takeaway. An angle on a circle graph is a percentage in a different language. A right angle always says a quarter.

Variant 11 hard answer: 135 students

The circle graph at the right shows the favorite snacks of the $300$ students in Jia's class. How many students like pizza?

Show solution

1 · Understandwhat's really being asked

300 students are split between four snacks. Chicken has 25 percent and Other 5 percent; the tteokbokki slice is a right angle and pizza is unlabelled. We want how many like pizza.

Givens

There are 300 students in the class.
Chicken is 25 percent and Other is 5 percent.
The tteokbokki slice has a right angle at the centre.

Unknowns

How many students like pizza.

Constraints

The four slices together are the whole class.

2 · Planchoose the strategy

#1 Draw a Diagram · also uses: #8 Analyze the Units#16 Count the Complement

Two of the four slices are labelled and a third is marked with a right angle, which is a percentage written in a different language. Translate it, then get the fourth slice as what is left of 100.

3 · Execute3 carry out the plan

1Read the right angle as a share

#1 Draw a Diagram 6.SP.B.4

A full turn round the centre is 360 degrees, and a right angle is 90 of them -- a quarter of the circle.

90 \div 360 = 0.25 = 25\%

Tteokbokki is 25 percent.

2Take the three known slices off 100

#16 Count the Complement 6.RP.A.3

The four slices make the whole class, so the rest is pizza.

100 - 25 - 5 - 25 = 45

Pizza is 45 percent.

3Turn the percent into students

#8 Analyze the Units 6.RP.A.3

45 percent of the 300 students.

300 \times 0.45 = 135

135 students like pizza.

Answer: 135 students

4 · Reviewdoes it hold up?

The four percentages add to 100, and 135 students is 45 percent of 300 -- both books balance.

Another way: Measuring the pizza slice's angle would give 162 degrees, and dividing that by 360 gives the same share; the right angle is quicker because it needs no protractor.

Standardsmin grade 6

6.SP.B.4 Display numerical data in plots (dot, histogram, box) — Reading a circle graph, including a slice marked by its angle.
6.RP.A.3 Use ratio and rate reasoning to solve problems — Turning the leftover percentage into a number of students.

💡Takeaway. An angle on a circle graph is a percentage in a different language. A right angle always says a quarter.

Variant 12 hard answer: 45 students

The circle graph at the right shows the favorite snacks of the $300$ students in Jia's class. How many students like pizza?

Show solution

1 · Understandwhat's really being asked

300 students are split between four snacks. Chicken has 35 percent and Other 25 percent; the tteokbokki slice is a right angle and pizza is unlabelled. We want how many like pizza.

Givens

There are 300 students in the class.
Chicken is 35 percent and Other is 25 percent.
The tteokbokki slice has a right angle at the centre.

Unknowns

How many students like pizza.

Constraints

The four slices together are the whole class.

2 · Planchoose the strategy

#1 Draw a Diagram · also uses: #8 Analyze the Units#16 Count the Complement

Two of the four slices are labelled and a third is marked with a right angle, which is a percentage written in a different language. Translate it, then get the fourth slice as what is left of 100.

3 · Execute3 carry out the plan

1Read the right angle as a share

#1 Draw a Diagram 6.SP.B.4

A full turn round the centre is 360 degrees, and a right angle is 90 of them -- a quarter of the circle.

90 \div 360 = 0.25 = 25\%

Tteokbokki is 25 percent.

2Take the three known slices off 100

#16 Count the Complement 6.RP.A.3

The four slices make the whole class, so the rest is pizza.

100 - 35 - 25 - 25 = 15

Pizza is 15 percent.

3Turn the percent into students

#8 Analyze the Units 6.RP.A.3

15 percent of the 300 students.

300 \times 0.15 = 45

45 students like pizza.

Answer: 45 students

4 · Reviewdoes it hold up?

The four percentages add to 100, and 45 students is 15 percent of 300 -- both books balance.

Another way: Measuring the pizza slice's angle would give 54 degrees, and dividing that by 360 gives the same share; the right angle is quicker because it needs no protractor.

Standardsmin grade 6

6.SP.B.4 Display numerical data in plots (dot, histogram, box) — Reading a circle graph, including a slice marked by its angle.
6.RP.A.3 Use ratio and rate reasoning to solve problems — Turning the leftover percentage into a number of students.

💡Takeaway. An angle on a circle graph is a percentage in a different language. A right angle always says a quarter.