Lesson 6

Using Circle Pieces

Est. Class Sessions: 2

Daily Practice and Problems

Teacher Notes
X

TIMS Task

Refer students to the Multiplication Strategies Menu for Larger Numbers.

Possible estimates are given.

    1. Estimate: 16,000; Exact: 15,520
    2. Estimate: 5600; Exact: 5544
    3. Estimate: 2100; Exact: 1820
    4. Estimate: 8000; Exact: 7976
    5. Estimate: 42,000; Exact: 42,840
    6. Estimate: 4800; Exact: 4440
  2. Round 388 to 400.
    40 × 400 = 16,000.
    So 40 × 388 will be a little less than 16,000.
  3. For Question 1D,
    1000 × 8 = 8000
    8 × 3 = 24
    8000 – 24 = 7976

P. What Is the Product?

First, estimate the answers to the following problems using convenient numbers. Then solve them using paper and pencil or mental math.

    1. 40 × 388 =
    2. 693 × 8 =
    3. 7 × 260 =
    4. 997 × 8 =
    5. 70 × 612 =
    6. 555 × 8 =
  2. Explain your estimation strategy for Question 1A.
  3. Choose a problem in Question 1 and show or tell how you can solve it using mental math.