Lesson 2

Tangrams

Est. Class Sessions: 2–3

Daily Practice and Problems

Teacher Notes
X

TIMS Bit

  1. 23
  2. 77
  3. 50
  4. 32
  5. 41
  6. 51
  7. 86
  8. 111
  9. 104
  1. Possible response: Instead of adding 9, I add 10 to the number and then subtract 1.

E. Adding Nine

Solve the problems. Look for patterns.

  1. 14 + 9 =
  2. 68 + 9 =
  3. 41 + 9 =
  4. 23 + 9 =
  5. 32 + 9 =
  6. 42 + 9 =
  7. 77 + 9 =
  8. 102 + 9 =
  9. 95 + 9 =
  1. Explain your strategy for adding nine.