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5th grade math · Unit 11: Expressions and equations

Times the sum, or plus it?

What this lesson shows

Fixes a mistake

5(9 + 3) is 5 times the sum, not 5 + (9 + 3).

The worked example

The lesson works this one step by step: 5(9 + 3). Then your kid tries one like it on paper.

The steps

  1. Not plus
  2. Write the × sign
  3. Parentheses first

Helping at home

A number written right against a parenthesis multiplies it: 5(9 + 3) means 5 × (9 + 3). Write the times sign in, work the parentheses first, then multiply.

If your kid gets stuck

Write the × sign you cannot see.

Watch it with Lux

With Lux, this lesson is a narrated video and a printed page your kid works on. Then Lux helps with the same math on their own worksheet, one question at a time.

See how Lux works

Standards

  • Common Core 5.OA.A.2
    Write simple expressions that record calculations with numbers, and interpret numerical expressions without evaluating them. For example, express the calculation "add 8 and 7, then multiply by 2" as 2 × (8 + 7). Recognize that 3 × (18932 + 921) is three times as large as 18932 + 921, without having to calculate the indicated sum or product.
Matches standards in 46 statesSee each state's code

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