Subtract 10/9 from 20/8, Solve 2 4/8

Subtract 10/9 from 20/8

1^st number: 2 4/8, 2^nd number: 1 1/9

20/8 - 10/9 is 25/18.

Find the least common denominator or LCM of the two denominators:
LCM of 8 and 9 is 72

Next, find the equivalent fraction of both fractional numbers with denominator 72
For the 1st fraction, since 8 × 9 = 72,
20/8 = 20 × 9/8 × 9 = 180/72
Likewise, for the 2nd fraction, since 9 × 8 = 72,
10/9 = 10 × 8/9 × 8 = 80/72
Subtract the two like fractions:
180/72 - 80/72 = 180 - 80/72 = 100/72
After reducing the fraction, the answer is 25/18
In mixed form: 17/18

MathStep (Works offline)

Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad