Math Intervention 3–5 Grade

Addition and Subtraction Concepts 107

Rigorous Problem Solving with the Concept of
Equal Differences 2

Joey announced that 84 – 68 = 86 – 70. Do you agree or
disagree?

Part A

Is Joey correct or incorrect? Use the number
line to prove you answer.

Part B

If 86 pennies were tossed in air and 39 of them landed on
heads, how many landed on tails?

Use a place value strategy to prove your answer.

Part C

If 65 pennies were tossed in air and 31 of them landed on
heads, how many landed on tails?

Use a place value strategy to prove your answer.

© 2016, Math Intervention: Grades 3–5, Jennifer Taylor-Cox, Routledge

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