Lesson 9

Estimate Fraction Sums

Est. Class Sessions: 1–2

Daily Practice and Problems

Teacher Notes
X

TIMS Task

    1. 340 pencils
    2. Possible response: I multiplied 5 × 60 + 5 × 8 = 300 + 40 = 340
    1. More pencils
    2. Possible response: 32 × 10 = 320 erasers They packed 20 less erasers than pencils.

FF. Pencils and Erasers

  1. Mr. Moreno's class is packaging pencils for the school fair. They are putting 5 pencils in each bag. When they finished, they had 68 bags of pencils.
    1. How many pencils did they pack into bags?
    2. Show or tell how you solved this problem.
  2. The students also packaged erasers into bags. They placed 10 pencil-top erasers into each bag. When they finished, they had 32 bags of erasers.
    1. Did the class package more pencils or more erasers?
    2. Show or tell how you decided.