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5th grade math · Unit 1: Decimal place value

The point stays put

What this lesson shows

Fixes a mistake

3.5 × 10 = 35: each digit takes the next place up. The point still sits between ones and tenths.

The worked example

The lesson works this one step by step: 3.5 × 10. Then your kid tries one like it on paper.

The steps

  1. A 0 on the end changes nothing
  2. Each digit moves left
  3. The point stays put

Helping at home

Times 10 moves each digit one place left, and times 100 two places. The point stays between the ones and the tenths. A 0 put on the end after the point changes nothing.

If your kid gets stuck

Put the number in a place value chart first.

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.A.2
    Explain patterns in the number of zeros of the product when multiplying a number by powers of 10, and explain patterns in the placement of the decimal point when a decimal is multiplied or divided by a power of 10. Use whole-number exponents to denote powers of 10.
Matches a standard in all 50 states and DCSee each state's code

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