Lesson 3

Estimate Products

Est. Class Sessions: 3

Daily Practice and Problems

Teacher Notes
X

TIMS Task

  1. Jerome took 1 hour from the 4 hours and changed it to 60 minutes. Then he added 60 minutes and 30 minutes to get 90 minutes. Now he can subtract: 90 minutes − 45 minutes = 45 minutes.
    1. 3 hours and 2 minutes
    2. 2 hours and 50 minutes
    3. 5 hours and 34 minutes
    4. 10 hours and 57 minutes

J. Subtracting Time

Jerome is traveling on a train. He is going to visit his aunt. The train ride is 4 hours and 30 minutes long. So far he has traveled for 2 hours and 45 minutes. Jerome wants to know how much longer the train ride is. He writes the following:

Jerome still has 1 hour and 45 minutes left on his train ride.

  1. Explain how Jerome changed 4 hours 30 minutes to 3 hours and 90 minutes. Why did he rewrite the problem?
  2. Solve these problems.
    1. 7 hours 18 minutes − 4 hours 16 minutes
    2. 5 hours 26 minutes − 2 hours 36 minutes
    3. 12 hours 28 minutes − 6 hours 54 minutes
    4. 17 hours 47 minutes − 6 hours 50 minutes