Skip Counting — Answer Key
Part A: Multiple Choice
Circle the best answer for each question.
1. Mia has 5 bags with 10 apples each. She counts the apples by 10s. How many apples in all?
A) 40
B) 45
C) 50
D) 55
Skip-counting by 10s five times gives 10, 20, 30, 40, 50. So 5 bags of 10 apples makes 50 apples total.
2. Which number does NOT belong in counting by 3s from 0?
A) 12
B) 15
C) 20
D) 21
Counting by 3s from 0 gives 0, 3, 6, 9, 12, 15, 18, 21, 24. 20 is skipped because 20 divided by 3 does not come out even.
3. Jake counts by 5s starting at 0. He says seven numbers. What is the last number he says?
A) 25
B) 30
C) 35
D) 40
Starting at 0 and adding 5 each time, the seven numbers Jake says are 0, 5, 10, 15, 20, 25, 30. The seventh one is 30.
4. What is the missing number? 9, 12, ___, 18, 21.
A) 13
B) 14
C) 15
D) 16
The list counts by 3s, so 12 + 3 = 15, which also matches since 15 + 3 = 18.
Part B: Fill in the Blank
Write the correct answer on each line.
1. Count by 3s: 0, 3, 6, 9, 12.
Adding 3 to 6 gives 9, and 9 + 3 = 12 matches the next number, so the count-by-3s rule holds.
2. Count backward by 5s: 100, 95, 90, 85, 80.
Subtracting 5 from 90 gives 85, which is also 5 more than 80, keeping the -5 pattern steady.
3. Count by 2s: 22, 24, 26, 28, 30.
The numbers go up by 2, so 22 + 2 = 24, which matches since 24 + 2 = 26, the next number in the list.
4. Count backward by 3s: 18, 15, 12, 9.
Going back by 3 each step, 12 - 3 = 9, staying with the -3 pattern.
5. Count by 10s: 110, 120, 130, 140, 150.
The pattern adds 10 each step, so 130 + 10 = 140, which is also 10 less than 150.