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4th grade math · Unit 5: Fractions

A whole number times a fraction

What this lesson shows

5 × 3/4 as five groups of 3/4, added with bars.

The worked example

The lesson works this one step by step: 5 × 3/4. Then your kid tries one like it on paper.

The steps

  1. Groups of the fraction
  2. Add the groups
  3. Multiply the top, keep the bottom

Helping at home

Read 5 × 3/4 as 5 groups of 3/4. Draw a bar for each group and add the shaded parts. Multiply the top; the parts stay the same, so the bottom does too.

If your kid gets stuck

Draw one bar for each group.

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 4.NF.B.4a
    Understand a fraction a/b as a multiple of 1/b. For example, use a visual fraction model to represent 5/4 as the product 5 × (1/4), recording the conclusion by the equation 5/4 = 5 × (1/4).
  • Common Core 4.NF.B.4b
    Understand a multiple of a/b as a multiple of 1/b, and use this understanding to multiply a fraction by a whole number. For example, use a visual fraction model to express 3 × (2/5) as 6 × (1/5), recognizing this product as 6/5. (In general, n × (a/b) = (n × a)/b.)
Matches standards in 47 statesSee each state's code

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