Lesson 4

Paper-and-Pencil Subtraction

Est. Class Sessions: 2–3

Daily Practice and Problems

Teacher Notes
X

TIMS Bit

Students can use counting by half hours to help them solve problems involving elapsed time.

  1. 1:30 PM.
  2. 390 minutes; Possible response:
    60 min. × 6 hrs. = 360 min.
    360 + 30 = 390 minutes

M. Counting by Half Hours

  1. The time is 7:00 AM. What time will it be in 61/2 hours?
  2. How many minutes will have passed? Show or tell how you know.