Lesson 6

Paper-and-Pencil Subtraction:
Compact Method

Est. Class Sessions: 2–3

Daily Practice and Problems

Teacher Notes
X

Have desk number lines and 200 Charts readily available.

  1. 60
  2. 50
  3. 20
  4. Possible response: I used friendly numbers; 40 − 20 = 20.

U. Addition and Subtraction

Circle the best estimate for each problem.

  1. 26                    60                    100                    45
    + 35
  2. 69                    35                    50                      25
    − 22
  3. 37                    10                     5                       20
    − 19
  4. Show or tell your estimation strategy for Question C.