Basic Mathematics

Skip Counting

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Skip Counting

Skip counting is counting forwards or backwards by a number other than 1. Here is an example:

Forward skip counting by 3s:

1612, 1615, 1618, 1621, 1624, 1627,...

In this example, you added 3 to the first number (1612) to obtain the next number (1615). Each time 3 is added to the newly obtained number, the next number is identified.

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Here is another example:

Backward skip counting by 2.5s:

8372.5, 8370, 8367.5, 8365, 8362.5...

In this example, you subtracted 2.5 from the first number (8372.5) to obtain the next number (8370). Each time 2.5 is subtracted from the newly obtained number, the next number is identified.

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Which number comes after 9.9 when skip counting by 1.1s?

Question 1 of 12

That's correct. Use forward skip counting by adding 1.1 to 9.9. 9.9 + 1.1 = 11

11.1 comes after 9.9 when counting by 1.2s. Forward skip counting means adding 1.1 to 9.9 to obtain the answer. Try again.

10.1 comes after 9.9 when forward skip counting by 0.2. Forward skip counting means adding 1.1 to 9.9 to obtain the answer. Try again.

8.8 comes before 9.9 when backward skip counting by 1.1s. Use forward skip counting to find the answer. Forward skip counting means adding 1.1 to 9.9 to obtain the answer. Try again.

Use forward skip counting. When forward skip counting by 1.1s, add 1.1 to the first number to obtain the next number.

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Which group of numbers shows forward skip counting by 1.25s?

3.25, 4, 5.25, 7, 8.25

6.25, 6.5, 6.75, 7, 7.25

0, 1.25, 3, 5.5, 6.75

6.25, 7.5, 8.75, 10, 11.25

Question 2 of 12

A forward skip counting by 1.25s sequence, starting with 3.25, would begin with these two numbers: 3.25, 4.5. Try again.

A forward skip counting by 1.25s sequence, starting with 6.25, would begin with these two numbers: 6.25, 7.5. Try again.

A forward skip counting by 1.25s sequence, starting with 0, would begin with these three numbers: 0, 1.25, 2.5. Try again.

That's correct. Each number in this forward skip counting by 1.25s sequence was obtained by adding 1.25s to the previous number.

In forward skip counting by 1.25s, the number 1.25 must be added to the first number to obtain the next number.

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Which number comes after 85 when skip counting by 5s?

Question 3 of 12

75 comes before 85 when backward skip counting by 10s. Use forward skip counting to find the answer. Forward skip counting by 5s means adding 5 to 85 to obtain the answer. Try again.

That's correct. Use forward skip counting by adding 5 to 85.
85 + 5 = 90

88 comes after 85 when forward skip counting by 3s. Forward skip counting by 5s means adding 5 to 85 to obtain the answer. Try again.

80 comes before 85 when backward skip counting by 5s. Use forward skip counting to find the answer. Forward skip counting by 5s means adding 5 to 85 to obtain the answer. Try again.

Use forward skip counting. When forward skip counting by 5s, add 5 to the first number to obtain the next number.

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Which number comes before 18 when skip counting by 3s?

Question 4 of 12

16 comes before 18 when backward skip counting by 2s. Backward skip counting by 3s means you subtract 3 from 18 to obtain the answer. Try again.

13 comes before 18 when backward skip counting by 5s. Backward skip counting by 3s means you subtract 3 from 18 to obtain the answer. Try again.

17 comes before 18 when counting by 1s. Backward skip counting by 3s means you subtract 3 from 18 to obtain the answer. Try again.

That's correct. Using backward skip counting, subtract 3 from 18.
18 − 3 = 15

Use backward skip counting. When backward skip counting by 3s, subtract 3 from the first number to obtain the next number.

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Which group of numbers shows forward skip counting by 4s?

Question 5 of 12

A forward skip counting by 4s sequence, starting with 6, would begin with these three numbers: 6, 10, 14. Try again.

A forward skip counting by 4s sequence, starting with 0, would begin with these three numbers: 0, 4, 8. Try again.

That's correct. Each number in this forward skip counting by 4s sequence was obtained by adding 4 to the previous number.

A forward skip counting by 4s sequence, starting with 4, would begin with these two numbers: 4, 8. Try again.

In forward skip counting by 4s, the number 4 must be added to the first number to obtain the next number.

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Which group of numbers shows backward skip counting by 7s?

360, 353, 346, 339, 332

517, 510, 507, 500, 497

367, 360, 362, 351, 345

277, 270, 263, 255, 250

Question 6 of 12

That's correct. Each number in this forward skip counting by 7s sequence was obtained by subtracting 7 from the previous number.

A backward skip counting by 7s sequence, starting with 517, would begin with these three numbers: 517, 510, 503. Try again.

A backward skip counting by 7s sequence, starting with 367, would begin with these three numbers: 367, 360, 353. Try again.

A backward skip counting by 7s sequence, starting with 277, would begin with these four numbers: 277, 270, 263, 256. Try again.

In backward skip counting by 7s, the number 7 must be subtracted from the first number to obtain the next number.

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Which number comes before 36 when skip counting by 12s?

Question 7 of 12

48 comes after 36 when forward skip counting by 12s. Use backward skip counting to find the answer. Backward skip counting by 12s means you subtract 12 from 36 to obtain the answer. Try again.

12 comes before 36 when backward skip counting by 24s. Backward skip counting by 12s means you subtract 12 from 36 to obtain the answer. Try again.

30 comes before 36 when backward skip counting by 6s. Backward skip counting by 12s means you subtract 12 from 36 to obtain the answer. Try again.

That's correct. Use backward skip counting by subtracting 12 from 36.
36 − 12 = 24.

Use backward skip counting. When backward skip counting by 12s, subtract 12 from the first number to obtain the next number.

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Which group of numbers shows backward skip counting by 3.5s?

49.5, 47.5, 45.5, 43.5, 41.5

49.5, 46, 42.5, 39, 35.5

35.5, 39, 42.5, 46, 49.5

15.5, 12, 9.5, 6, 3.5

Question 8 of 12

A backward skip counting by 3.5s sequence, starting with 49.5, would begin with these two numbers: 49.5, 46. Try again.

That's correct. Each number in this backward skip counting by 3.5 sequence was obtained by subtracting 3.5 from the previous number.

This is a forward skip counting sequence. A backward skip counting by 3.5s sequence subtracts 3.5 from the first number to obtain the next number. Try again.

A backward skip counting by 3.5s sequence, starting with 15.5, would begin with these three numbers: 15.5, 12, 8.5. Try again.

In backward skip counting by 3.5s, the number 3.5 must be subtracted from the first number to obtain the next number.

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Which number comes after 21.25 when skip counting by 2.75s?

Question 9 of 12

23.25 comes after 21.25 when forward skip counting by 2s. Forward skip counting by 2.75s means adding 2.75 to 21.25 to obtain the answer. Try again.

24.75 comes after 21.25 when forward skip counting by 3.5s. Forward skip counting by 2.75s means adding 2.75 to 21.25 to obtain the answer. Try again.

That's correct. Use forward skip counting by adding 2.75 to 21.25.
21.25 + 2.75 = 24

24.5 comes after 21.25 when forward skip counting by 3.25s. Forward skip counting by 2.75s means adding 2.75 to 21.25 to obtain the answer. Try again.

Use forward skip counting. When forward skip counting by 2.75s, add 2.75 to the first number to obtain the next number.

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Which number comes before 6.75 when skip counting by 1.25s?

Question 10 of 12

5.75 comes before 6.75 when counting by 1s. Backward skip counting by 1.25s means you subtract 1.25 from 6.75 to obtain the answer. Try again.

That's correct. Use backward skip counting by subtracting 1.25 from 6.75.
6.75 − 1.25 = 5.5

6.25 comes before 6.75 when backward skip counting by 0.5s. Backward skip counting by 1.25s means you subtract 1.25 from 6.75 to obtain the answer. Try again.

6.5 comes before 6.75 when backward skip counting by 0.25s. Backward skip counting by 1.25s means you subtract 1.25 from 6.75 to obtain the answer. Try again.

Use backward skip counting. When backward skip counting by 1.25s, subtract 1.25 from the first number to obtain the next number.

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Which group of numbers shows forward skip counting by 2s?

⁻50, ⁻40, ⁻30, ⁻20, ⁻10

⁻2, ⁻4, ⁻6, ⁻8, ⁻10

⁻14, ⁻12, ⁻10, ⁻8, ⁻6

⁻12, ⁻8, ⁻4, 0, 4

Question 11 of 12

A forward skip counting by 2s sequence, starting with ⁻50, would begin with these two numbers: ⁻50, ⁻48. Try again.

This shows backward skip counting by 2s. The number 2 is subtracted from the first number to obtain the next number. Try again.

That's correct. Each number in this forward skip counting by 2s sequence was obtained by adding 2 to the previous number.

A forward skip counting by 2s sequence, starting with ⁻12, would begin with these two numbers: ⁻12, ⁻10. Try again.

In forward skip counting by 2s, the number 2 must be added to the first number to obtain the next number.

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Which group of numbers shows forward skip counting by 2.1s?

2.1, 3.2, 4.3, 5.4, 6.5

3.3, 5.4, 7.5, 9.6, 11.7

3.3, 4.4, 5.5, 6.6, 7.7

2.1, 4.2, 6.4, 8.5, 10.6

Question 12 of 12

A forward skip counting by 2.1s sequence, starting with 2.1, would begin with these two numbers: 2.1, 4.2. Try again.

That's correct. Each number in this forward skip counting by 2.1s sequence was obtained by adding 2.1 to the previous number.

A forward skip counting by 2.1s sequence, starting with 3.3, would begin with these two numbers: 3.3, 5.4. Try again.

A forward skip counting by 2.1s sequence, starting with 2.1, would begin with these three numbers: 2.1, 4.2, 6.3. Try again.

In forward skip counting by 2.1s, the number 2.1 must be added to the first number to obtain the next number.

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