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5th grade math · Unit 5: Multiplying and dividing decimals

Estimating decimal answers

What this lesson shows

82 × 0.56 is between 41 and 82, since 0.56 is a bit more than one half.

The worked example

The lesson works this one step by step: 82 × 0.56. Then your kid tries one like it on paper.

The steps

  1. Place the decimal between 0 and 1
  2. Times one half, times 1
  3. Between the two, near the closer

Helping at home

Compare the decimal with one half and 1 on a number line. Times one half is half the number; times 1 is the number. The product lies between, near the closer one. Estimate only; no long multiplication on this page.

If your kid gets stuck

Is the decimal near one half or near 1?

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.NBT.B.7
    Add, subtract, multiply, and divide decimals to hundredths, using concrete models or drawings and strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; relate the strategy to a written method and explain the reasoning used.
Matches a standard in all 50 states and DCSee each state's code

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