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← 2-2 · Find the constant skip-count step · Generalize a Growing Pattern into a Rule

Find the constant skip-count step · 10 practice problems

4.NBT.A.22.NBT.A.2

Generated variants — 10

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

Variant 1 answer: 200

The numbers below were made by skip-counting by \bullet, shown on a number line. Find the value of \bullet.

A number line has four evenly spaced tick marks. Reading from left to right, they are labeled 25002500, 27002700, 29002900, 31003100. The gap between each pair of neighboring numbers is the same, and the numbers were made by skip-counting by that amount.

2500 2700 2900 3100
Show solution

Understand

On a number line, four evenly spaced ticks read 2500, 2700, 2900, 3100 from left to right. The numbers were made by skip-counting by the same step each time. Find that step.

Givens
  • The labeled numbers, left to right, are 2500, 2700, 2900, 3100.
  • The ticks are evenly spaced, so the gap between neighbors is constant.
  • The numbers were made by skip-counting by that constant gap.
Unknowns
  • The size of each skip-count step (the value of the dot).
Constraints
  • Every neighboring pair differs by the same amount.

Plan

#5 Look for a Pattern · also uses: #1 Draw a Diagram

Equally spaced numbers on a number line are a repeated-structure pattern, so I find the constant difference between two neighboring labels and confirm it repeats.

Execute

#5 Look for a Pattern 4.NBT.A.2
Subtract a number from the one just after it: 2700 minus 2500 is 200. So one skip is 200.
27002500=2002700 - 2500 = 200
The change from one tick to the next is exactly one skip, found by subtracting.
#1 Draw a Diagram 2.NBT.A.2
Check the other gaps: each neighboring pair also differs by 200. Every gap is 200, so the skip-count step is 200.
29002700=200,31002900=2002900 - 2700 = 200,\quad 3100 - 2900 = 200
If each evenly spaced jump is the same 200, the pattern is just counting by 200.
Answer: 200

Review

Counting on by 200 from 2500 gives 2700, 2900, 3100, exactly the labels shown, so a step of 200 is correct.

Compare the first and last numbers: 3100 minus 2500 is 600, spread over 3 equal jumps, so each jump is 600 divided by 3, which is 200.

Standards · min grade 4

  • 4.NBT.A.2 Read and write multi-digit whole numbers and compare using symbols — Subtracting neighboring multi-digit labels to find the constant gap.
  • 2.NBT.A.2 Count within 1000, skip-count by 5s, 10s, and 100s — Recognizing the evenly spaced labels as skip-counting by a fixed step.
💡 Subtract one tick from the next and you've found the skip size!
Variant 2 answer: 500

The numbers below were made by skip-counting by \bullet, shown on a number line. Find the value of \bullet.

A number line has four evenly spaced tick marks. Reading from left to right, they are labeled 40604060, 45604560, 50605060, 55605560. The gap between each pair of neighboring numbers is the same, and the numbers were made by skip-counting by that amount.

4060 4560 5060 5560
Show solution

Understand

On a number line, four evenly spaced ticks read 4060, 4560, 5060, 5560 from left to right. The numbers were made by skip-counting by the same step each time. Find that step.

Givens
  • The labeled numbers, left to right, are 4060, 4560, 5060, 5560.
  • The ticks are evenly spaced, so the gap between neighbors is constant.
  • The numbers were made by skip-counting by that constant gap.
Unknowns
  • The size of each skip-count step (the value of the dot).
Constraints
  • Every neighboring pair differs by the same amount.

Plan

#5 Look for a Pattern · also uses: #1 Draw a Diagram

Equally spaced numbers on a number line are a repeated-structure pattern, so I find the constant difference between two neighboring labels and confirm it repeats.

Execute

#5 Look for a Pattern 4.NBT.A.2
Subtract a number from the one just after it: 4560 minus 4060 is 500. So one skip is 500.
45604060=5004560 - 4060 = 500
The change from one tick to the next is exactly one skip, found by subtracting.
#1 Draw a Diagram 2.NBT.A.2
Check the other gaps: each neighboring pair also differs by 500. Every gap is 500, so the skip-count step is 500.
50604560=500,55605060=5005060 - 4560 = 500,\quad 5560 - 5060 = 500
If each evenly spaced jump is the same 500, the pattern is just counting by 500.
Answer: 500

Review

Counting on by 500 from 4060 gives 4560, 5060, 5560, exactly the labels shown, so a step of 500 is correct.

Compare the first and last numbers: 5560 minus 4060 is 1500, spread over 3 equal jumps, so each jump is 1500 divided by 3, which is 500.

Standards · min grade 4

  • 4.NBT.A.2 Read and write multi-digit whole numbers and compare using symbols — Subtracting neighboring multi-digit labels to find the constant gap.
  • 2.NBT.A.2 Count within 1000, skip-count by 5s, 10s, and 100s — Recognizing the evenly spaced labels as skip-counting by a fixed step.
💡 Subtract one tick from the next and you've found the skip size!
Variant 3 answer: 10

The numbers below were made by skip-counting by \bullet, shown on a number line. Find the value of \bullet.

A number line has five evenly spaced tick marks. Reading from left to right, they are labeled 11111111, 11211121, 11311131, 11411141, 11511151. The gap between each pair of neighboring numbers is the same, and the numbers were made by skip-counting by that amount.

1111 1121 1131 1141 1151
Show solution

Understand

On a number line, five evenly spaced ticks read 1111, 1121, 1131, 1141, 1151 from left to right. The numbers were made by skip-counting by the same step each time. Find that step.

Givens
  • The labeled numbers, left to right, are 1111, 1121, 1131, 1141, 1151.
  • The ticks are evenly spaced, so the gap between neighbors is constant.
  • The numbers were made by skip-counting by that constant gap.
Unknowns
  • The size of each skip-count step (the value of the dot).
Constraints
  • Every neighboring pair differs by the same amount.

Plan

#5 Look for a Pattern · also uses: #1 Draw a Diagram

Equally spaced numbers on a number line are a repeated-structure pattern, so I find the constant difference between two neighboring labels and confirm it repeats.

Execute

#5 Look for a Pattern 4.NBT.A.2
Subtract a number from the one just after it: 1121 minus 1111 is 10. So one skip is 10.
11211111=101121 - 1111 = 10
The change from one tick to the next is exactly one skip, found by subtracting.
#1 Draw a Diagram 2.NBT.A.2
Check the other gaps: each neighboring pair also differs by 10. Every gap is 10, so the skip-count step is 10.
11311121=10,11411131=10,11511141=101131 - 1121 = 10,\quad 1141 - 1131 = 10,\quad 1151 - 1141 = 10
If each evenly spaced jump is the same 10, the pattern is just counting by 10.
Answer: 10

Review

Counting on by 10 from 1111 gives 1121, 1131, 1141, 1151, exactly the labels shown, so a step of 10 is correct.

Compare the first and last numbers: 1151 minus 1111 is 40, spread over 4 equal jumps, so each jump is 40 divided by 4, which is 10.

Standards · min grade 4

  • 4.NBT.A.2 Read and write multi-digit whole numbers and compare using symbols — Subtracting neighboring multi-digit labels to find the constant gap.
  • 2.NBT.A.2 Count within 1000, skip-count by 5s, 10s, and 100s — Recognizing the evenly spaced labels as skip-counting by a fixed step.
💡 Subtract one tick from the next and you've found the skip size!
Variant 4 answer: 1000

The numbers below were made by skip-counting by \bullet, shown on a number line. Find the value of \bullet.

A number line has five evenly spaced tick marks. Reading from left to right, they are labeled 20082008, 30083008, 40084008, 50085008, 60086008. The gap between each pair of neighboring numbers is the same, and the numbers were made by skip-counting by that amount.

2008 3008 4008 5008 6008
Show solution

Understand

On a number line, five evenly spaced ticks read 2008, 3008, 4008, 5008, 6008 from left to right. The numbers were made by skip-counting by the same step each time. Find that step.

Givens
  • The labeled numbers, left to right, are 2008, 3008, 4008, 5008, 6008.
  • The ticks are evenly spaced, so the gap between neighbors is constant.
  • The numbers were made by skip-counting by that constant gap.
Unknowns
  • The size of each skip-count step (the value of the dot).
Constraints
  • Every neighboring pair differs by the same amount.

Plan

#5 Look for a Pattern · also uses: #1 Draw a Diagram

Equally spaced numbers on a number line are a repeated-structure pattern, so I find the constant difference between two neighboring labels and confirm it repeats.

Execute

#5 Look for a Pattern 4.NBT.A.2
Subtract a number from the one just after it: 3008 minus 2008 is 1000. So one skip is 1000.
30082008=10003008 - 2008 = 1000
The change from one tick to the next is exactly one skip, found by subtracting.
#1 Draw a Diagram 2.NBT.A.2
Check the other gaps: each neighboring pair also differs by 1000. Every gap is 1000, so the skip-count step is 1000.
40083008=1000,50084008=1000,60085008=10004008 - 3008 = 1000,\quad 5008 - 4008 = 1000,\quad 6008 - 5008 = 1000
If each evenly spaced jump is the same 1000, the pattern is just counting by 1000.
Answer: 1000

Review

Counting on by 1000 from 2008 gives 3008, 4008, 5008, 6008, exactly the labels shown, so a step of 1000 is correct.

Compare the first and last numbers: 6008 minus 2008 is 4000, spread over 4 equal jumps, so each jump is 4000 divided by 4, which is 1000.

Standards · min grade 4

  • 4.NBT.A.2 Read and write multi-digit whole numbers and compare using symbols — Subtracting neighboring multi-digit labels to find the constant gap.
  • 2.NBT.A.2 Count within 1000, skip-count by 5s, 10s, and 100s — Recognizing the evenly spaced labels as skip-counting by a fixed step.
💡 Subtract one tick from the next and you've found the skip size!
Variant 5 answer: 100

The numbers below were made by skip-counting by \bullet, shown on a number line. Find the value of \bullet.

A number line has five evenly spaced tick marks. Reading from left to right, they are labeled 30153015, 31153115, 32153215, 33153315, 34153415. The gap between each pair of neighboring numbers is the same, and the numbers were made by skip-counting by that amount.

3015 3115 3215 3315 3415
Show solution

Understand

On a number line, five evenly spaced ticks read 3015, 3115, 3215, 3315, 3415 from left to right. The numbers were made by skip-counting by the same step each time. Find that step.

Givens
  • The labeled numbers, left to right, are 3015, 3115, 3215, 3315, 3415.
  • The ticks are evenly spaced, so the gap between neighbors is constant.
  • The numbers were made by skip-counting by that constant gap.
Unknowns
  • The size of each skip-count step (the value of the dot).
Constraints
  • Every neighboring pair differs by the same amount.

Plan

#5 Look for a Pattern · also uses: #1 Draw a Diagram

Equally spaced numbers on a number line are a repeated-structure pattern, so I find the constant difference between two neighboring labels and confirm it repeats.

Execute

#5 Look for a Pattern 4.NBT.A.2
Subtract a number from the one just after it: 3115 minus 3015 is 100. So one skip is 100.
31153015=1003115 - 3015 = 100
The change from one tick to the next is exactly one skip, found by subtracting.
#1 Draw a Diagram 2.NBT.A.2
Check the other gaps: each neighboring pair also differs by 100. Every gap is 100, so the skip-count step is 100.
32153115=100,33153215=100,34153315=1003215 - 3115 = 100,\quad 3315 - 3215 = 100,\quad 3415 - 3315 = 100
If each evenly spaced jump is the same 100, the pattern is just counting by 100.
Answer: 100

Review

Counting on by 100 from 3015 gives 3115, 3215, 3315, 3415, exactly the labels shown, so a step of 100 is correct.

Compare the first and last numbers: 3415 minus 3015 is 400, spread over 4 equal jumps, so each jump is 400 divided by 4, which is 100.

Standards · min grade 4

  • 4.NBT.A.2 Read and write multi-digit whole numbers and compare using symbols — Subtracting neighboring multi-digit labels to find the constant gap.
  • 2.NBT.A.2 Count within 1000, skip-count by 5s, 10s, and 100s — Recognizing the evenly spaced labels as skip-counting by a fixed step.
💡 Subtract one tick from the next and you've found the skip size!
Variant 6 answer: 10

The numbers below were made by skip-counting by \bullet, shown on a number line. Find the value of \bullet.

A number line has four evenly spaced tick marks. Reading from left to right, they are labeled 12001200, 12101210, 12201220, 12301230. The gap between each pair of neighboring numbers is the same, and the numbers were made by skip-counting by that amount.

1200 1210 1220 1230
Show solution

Understand

On a number line, four evenly spaced ticks read 1200, 1210, 1220, 1230 from left to right. The numbers were made by skip-counting by the same step each time. Find that step.

Givens
  • The labeled numbers, left to right, are 1200, 1210, 1220, 1230.
  • The ticks are evenly spaced, so the gap between neighbors is constant.
  • The numbers were made by skip-counting by that constant gap.
Unknowns
  • The size of each skip-count step (the value of the dot).
Constraints
  • Every neighboring pair differs by the same amount.

Plan

#5 Look for a Pattern · also uses: #1 Draw a Diagram

Equally spaced numbers on a number line are a repeated-structure pattern, so I find the constant difference between two neighboring labels and confirm it repeats.

Execute

#5 Look for a Pattern 4.NBT.A.2
Subtract a number from the one just after it: 1210 minus 1200 is 10. So one skip is 10.
12101200=101210 - 1200 = 10
The change from one tick to the next is exactly one skip, found by subtracting.
#1 Draw a Diagram 2.NBT.A.2
Check the other gaps: each neighboring pair also differs by 10. Every gap is 10, so the skip-count step is 10.
12201210=10,12301220=101220 - 1210 = 10,\quad 1230 - 1220 = 10
If each evenly spaced jump is the same 10, the pattern is just counting by 10.
Answer: 10

Review

Counting on by 10 from 1200 gives 1210, 1220, 1230, exactly the labels shown, so a step of 10 is correct.

Compare the first and last numbers: 1230 minus 1200 is 30, spread over 3 equal jumps, so each jump is 30 divided by 3, which is 10.

Standards · min grade 4

  • 4.NBT.A.2 Read and write multi-digit whole numbers and compare using symbols — Subtracting neighboring multi-digit labels to find the constant gap.
  • 2.NBT.A.2 Count within 1000, skip-count by 5s, 10s, and 100s — Recognizing the evenly spaced labels as skip-counting by a fixed step.
💡 Subtract one tick from the next and you've found the skip size!
Variant 7 answer: 100

The numbers below were made by skip-counting by \bullet, shown on a number line. Find the value of \bullet.

A number line has four evenly spaced tick marks. Reading from left to right, they are labeled 38293829, 39293929, 40294029, 41294129. The gap between each pair of neighboring numbers is the same, and the numbers were made by skip-counting by that amount.

3829 3929 4029 4129
Show solution

Understand

On a number line, four evenly spaced ticks read 3829, 3929, 4029, 4129 from left to right. The numbers were made by skip-counting by the same step each time. Find that step.

Givens
  • The labeled numbers, left to right, are 3829, 3929, 4029, 4129.
  • The ticks are evenly spaced, so the gap between neighbors is constant.
  • The numbers were made by skip-counting by that constant gap.
Unknowns
  • The size of each skip-count step (the value of the dot).
Constraints
  • Every neighboring pair differs by the same amount.

Plan

#5 Look for a Pattern · also uses: #1 Draw a Diagram

Equally spaced numbers on a number line are a repeated-structure pattern, so I find the constant difference between two neighboring labels and confirm it repeats.

Execute

#5 Look for a Pattern 4.NBT.A.2
Subtract a number from the one just after it: 3929 minus 3829 is 100. So one skip is 100.
39293829=1003929 - 3829 = 100
The change from one tick to the next is exactly one skip, found by subtracting.
#1 Draw a Diagram 2.NBT.A.2
Check the other gaps: each neighboring pair also differs by 100. Every gap is 100, so the skip-count step is 100.
40293929=100,41294029=1004029 - 3929 = 100,\quad 4129 - 4029 = 100
If each evenly spaced jump is the same 100, the pattern is just counting by 100.
Answer: 100

Review

Counting on by 100 from 3829 gives 3929, 4029, 4129, exactly the labels shown, so a step of 100 is correct.

Compare the first and last numbers: 4129 minus 3829 is 300, spread over 3 equal jumps, so each jump is 300 divided by 3, which is 100.

Standards · min grade 4

  • 4.NBT.A.2 Read and write multi-digit whole numbers and compare using symbols — Subtracting neighboring multi-digit labels to find the constant gap.
  • 2.NBT.A.2 Count within 1000, skip-count by 5s, 10s, and 100s — Recognizing the evenly spaced labels as skip-counting by a fixed step.
💡 Subtract one tick from the next and you've found the skip size!
Variant 8 answer: 50

The numbers below were made by skip-counting by \bullet, shown on a number line. Find the value of \bullet.

A number line has four evenly spaced tick marks. Reading from left to right, they are labeled 52305230, 52805280, 53305330, 53805380. The gap between each pair of neighboring numbers is the same, and the numbers were made by skip-counting by that amount.

5230 5280 5330 5380
Show solution

Understand

On a number line, four evenly spaced ticks read 5230, 5280, 5330, 5380 from left to right. The numbers were made by skip-counting by the same step each time. Find that step.

Givens
  • The labeled numbers, left to right, are 5230, 5280, 5330, 5380.
  • The ticks are evenly spaced, so the gap between neighbors is constant.
  • The numbers were made by skip-counting by that constant gap.
Unknowns
  • The size of each skip-count step (the value of the dot).
Constraints
  • Every neighboring pair differs by the same amount.

Plan

#5 Look for a Pattern · also uses: #1 Draw a Diagram

Equally spaced numbers on a number line are a repeated-structure pattern, so I find the constant difference between two neighboring labels and confirm it repeats.

Execute

#5 Look for a Pattern 4.NBT.A.2
Subtract a number from the one just after it: 5280 minus 5230 is 50. So one skip is 50.
52805230=505280 - 5230 = 50
The change from one tick to the next is exactly one skip, found by subtracting.
#1 Draw a Diagram 2.NBT.A.2
Check the other gaps: each neighboring pair also differs by 50. Every gap is 50, so the skip-count step is 50.
53305280=50,53805330=505330 - 5280 = 50,\quad 5380 - 5330 = 50
If each evenly spaced jump is the same 50, the pattern is just counting by 50.
Answer: 50

Review

Counting on by 50 from 5230 gives 5280, 5330, 5380, exactly the labels shown, so a step of 50 is correct.

Compare the first and last numbers: 5380 minus 5230 is 150, spread over 3 equal jumps, so each jump is 150 divided by 3, which is 50.

Standards · min grade 4

  • 4.NBT.A.2 Read and write multi-digit whole numbers and compare using symbols — Subtracting neighboring multi-digit labels to find the constant gap.
  • 2.NBT.A.2 Count within 1000, skip-count by 5s, 10s, and 100s — Recognizing the evenly spaced labels as skip-counting by a fixed step.
💡 Subtract one tick from the next and you've found the skip size!
Variant 9 answer: 200

The numbers below were made by skip-counting by \bullet, shown on a number line. Find the value of \bullet.

A number line has four evenly spaced tick marks. Reading from left to right, they are labeled 64006400, 66006600, 68006800, 70007000. The gap between each pair of neighboring numbers is the same, and the numbers were made by skip-counting by that amount.

6400 6600 6800 7000
Show solution

Understand

On a number line, four evenly spaced ticks read 6400, 6600, 6800, 7000 from left to right. The numbers were made by skip-counting by the same step each time. Find that step.

Givens
  • The labeled numbers, left to right, are 6400, 6600, 6800, 7000.
  • The ticks are evenly spaced, so the gap between neighbors is constant.
  • The numbers were made by skip-counting by that constant gap.
Unknowns
  • The size of each skip-count step (the value of the dot).
Constraints
  • Every neighboring pair differs by the same amount.

Plan

#5 Look for a Pattern · also uses: #1 Draw a Diagram

Equally spaced numbers on a number line are a repeated-structure pattern, so I find the constant difference between two neighboring labels and confirm it repeats.

Execute

#5 Look for a Pattern 4.NBT.A.2
Subtract a number from the one just after it: 6600 minus 6400 is 200. So one skip is 200.
66006400=2006600 - 6400 = 200
The change from one tick to the next is exactly one skip, found by subtracting.
#1 Draw a Diagram 2.NBT.A.2
Check the other gaps: each neighboring pair also differs by 200. Every gap is 200, so the skip-count step is 200.
68006600=200,70006800=2006800 - 6600 = 200,\quad 7000 - 6800 = 200
If each evenly spaced jump is the same 200, the pattern is just counting by 200.
Answer: 200

Review

Counting on by 200 from 6400 gives 6600, 6800, 7000, exactly the labels shown, so a step of 200 is correct.

Compare the first and last numbers: 7000 minus 6400 is 600, spread over 3 equal jumps, so each jump is 600 divided by 3, which is 200.

Standards · min grade 4

  • 4.NBT.A.2 Read and write multi-digit whole numbers and compare using symbols — Subtracting neighboring multi-digit labels to find the constant gap.
  • 2.NBT.A.2 Count within 1000, skip-count by 5s, 10s, and 100s — Recognizing the evenly spaced labels as skip-counting by a fixed step.
💡 Subtract one tick from the next and you've found the skip size!
Variant 10 answer: 1000

The numbers below were made by skip-counting by \bullet, shown on a number line. Find the value of \bullet.

A number line has four evenly spaced tick marks. Reading from left to right, they are labeled 10001000, 20002000, 30003000, 40004000. The gap between each pair of neighboring numbers is the same, and the numbers were made by skip-counting by that amount.

1000 2000 3000 4000
Show solution

Understand

On a number line, four evenly spaced ticks read 1000, 2000, 3000, 4000 from left to right. The numbers were made by skip-counting by the same step each time. Find that step.

Givens
  • The labeled numbers, left to right, are 1000, 2000, 3000, 4000.
  • The ticks are evenly spaced, so the gap between neighbors is constant.
  • The numbers were made by skip-counting by that constant gap.
Unknowns
  • The size of each skip-count step (the value of the dot).
Constraints
  • Every neighboring pair differs by the same amount.

Plan

#5 Look for a Pattern · also uses: #1 Draw a Diagram

Equally spaced numbers on a number line are a repeated-structure pattern, so I find the constant difference between two neighboring labels and confirm it repeats.

Execute

#5 Look for a Pattern 4.NBT.A.2
Subtract a number from the one just after it: 2000 minus 1000 is 1000. So one skip is 1000.
20001000=10002000 - 1000 = 1000
The change from one tick to the next is exactly one skip, found by subtracting.
#1 Draw a Diagram 2.NBT.A.2
Check the other gaps: each neighboring pair also differs by 1000. Every gap is 1000, so the skip-count step is 1000.
30002000=1000,40003000=10003000 - 2000 = 1000,\quad 4000 - 3000 = 1000
If each evenly spaced jump is the same 1000, the pattern is just counting by 1000.
Answer: 1000

Review

Counting on by 1000 from 1000 gives 2000, 3000, 4000, exactly the labels shown, so a step of 1000 is correct.

Compare the first and last numbers: 4000 minus 1000 is 3000, spread over 3 equal jumps, so each jump is 3000 divided by 3, which is 1000.

Standards · min grade 4

  • 4.NBT.A.2 Read and write multi-digit whole numbers and compare using symbols — Subtracting neighboring multi-digit labels to find the constant gap.
  • 2.NBT.A.2 Count within 1000, skip-count by 5s, 10s, and 100s — Recognizing the evenly spaced labels as skip-counting by a fixed step.
💡 Subtract one tick from the next and you've found the skip size!