Practice A

Show your thinking; use diagrams when they help. Do not open solutions during your first attempt.

Check your work: Finish the problems first, then ask a parent or instructor to review them with the separate answer-key copy.

1. A1

   There are 6 equal trays with 4 counters on each tray. How many counters are there?

2. A2

   There are 7 equal trays with 3 counters on each tray. How many counters are there?

3. A3

   An array has 7 rows, with 3 objects in each row. Split it into smaller arrays and find the total.

4. A4

   Each tray holds 7 counters. How many full trays are required to arrange 28 counters?

5. A5

   Compute 6 × 10. Explain a strategy using a known fact.

6. A6

   Compute 7 × 5. Explain a strategy using a known fact.

7. A7

   Use two useful multiplication facts to work out 6 × 10. What is the product?

8. A8

   70 counters are shared equally into 7 groups. How many counters are in each group?

9. A9

   Find 6 groups of 6. Can you use 5 groups plus one more?

10. A10

    Find 7 groups of 9. Can you use 6 groups plus one more?

11. A11

    Explain how splitting 7 equal groups of 7 helps you find their total.

12. A12

    42 counters are shared equally into 6 groups. How many counters are in each group?

13. A13

    There are 6 equal trays with 9 counters on each tray. How many counters are there?

14. A14

    There are 7 equal trays with 5 counters on each tray. How many counters are there?

15. A15

    An array has 6 rows, with 8 objects in each row. Split it into smaller arrays and find the total.

16. A16

    Each tray holds 7 counters. How many full trays are required to arrange 21 counters?

17. A17

    An array has 7 rows of 6 dots. A student says turning it creates 6 more dots. Explain the error and find the total.

18. A18

    Without counting individual counters, show two different decompositions for 6 × 5, and explain why both work.