4. Subtracting fractions — Learner Route

Fractions · Step 4

Subtracting fractions

Start with a fraction, remove some equal-sized pieces, and see what remains. If the pieces are different sizes, make one familiar refinement first.

Look first

Six eighths take away two eighths

The pieces are already the same size. Start with six eighths and remove two of them.

6/8
Notice

The piece size stays the same

6/8 − 2/8 = 4/8
The denominator
The denominator still tells us the size of each piece. We are still using eighths.
The numerator
The numerator tells us how many pieces remain. We start with 6 pieces and remove 2.
Now the pieces differ

Three quarters take away one half

A half is not the same size as a quarter. Rewrite the half as two quarters before removing it.

3/4
−
1/2
Interactive lab

What remains?

Look at the pieces, then choose the fraction left after subtraction.

Choose an answer.
Method Trainer

Subtract familiar fractions

Try five new examples. Your answers feed into your Practice Lab log on this device.

Question 1 of 5 · 0 answered

Type the answer as a fraction, whole number or decimal. Equivalent fractions are accepted.

You have learned

When fraction pieces are the same size, keep that piece size and subtract the number of pieces.

If the pieces differ, use a familiar equivalent fraction first — such as changing one half into two quarters — then remove equal-sized pieces.