Lesson 10

Multiplication Strategies

Est. Class Sessions: 1

Daily Practice and Problems

Teacher Notes
X

TIMS Challenge

Answers will vary.

  1. 16 or 49
    Possible explanation: The square numbers are on the longest diagonal on the Facts I Know chart. The squares larger than 9: 16, 25, 36, 49, 64, 81, 100. Both 16 and 49 have one digit that is 5 more than the other.
  2. 25 or 64
    Possible explanation: Looking at the squares on the diagonal, I see that 2 × 6 = 12 and 12 − 4 = 8, so 64 works.
  3. Answers will vary. Have some students present their riddles to the whole class.

JJ. Who Am I?

Show or tell how you solve each riddle.

  1. I am a square number greater than 9. One of my two digits is 5 more than the other. Who am I?
  2. I am a square number less than 100. One of my digits is 8 less than twice the other. Who am I?
  3. Make up your own square number riddle and try it on a partner.