EN
BuilderGrades 3–4⏱ 15 min

Equivalent fractions

Slice a fraction bar into smaller pieces and watch the numbers change while the amount stays the same.

Standards: 3.NF.A.34.NF.A.1

1Wonder

Maya ate 1/2 of a chocolate bar. Leo ate 2/4 of the same kind of bar. Leo says he ate more because 2 and 4 are bigger numbers. Is he right?

2Explore

Fraction slicer

This activity needs a bigger screen

Turn your phone sideways, or open this lesson on a tablet or computer. The explanation and quiz below work here.

341/21/31/4= 3/41/51/61/8= 6/81/101/12= 9/12SillyChili
Equal fractions on the wall: 3/4 = 6/8 = 9/12
Equal parts
4
Shaded parts
3
Cut each part into
1
Try this
  • Make 3/4. Then cut each part into 2 pieces. What fraction do you see now? Did the shaded amount change?
  • Look at the fraction wall. Which rows have a block that ends exactly on the red line?
  • Make 1/2. How many equal fractions can you find on the wall?
  • Make 2/5. Why does only one other row light up?

3Explain

1224SillyChili
Step 1 of 5

Same amount, different names

1/2 and 2/4 cover exactly the same part of the bar. Fractions that name the same amount are called equivalent fractions.

Equivalent fractionsab=a×kb×k\frac{a}{b} = \frac{a \times k}{b \times k}

Multiply (or divide) the top and the bottom by the same number, and you get a fraction for the same amount.

4Practice

Question 1 of 5

1/2 = ?/8

5Recap

  • Equivalent fractions name the same amount, like 1/2 = 2/4 = 3/6.
  • Multiply the top and bottom by the same number to get an equivalent fraction.
  • Divide the top and bottom by the same number to simplify.
  • Equivalent fractions sit on the same point of the number line.