Subtract 25/35 from 21/18, Solve 1 3/18

Subtract 25/35 from 21/18

1^st number: 1 3/18, 2^nd number: 25/35

21/18 - 25/35 is 19/42.

Find the least common denominator or LCM of the two denominators:
LCM of 18 and 35 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 18 × 35 = 630,
21/18 = 21 × 35/18 × 35 = 735/630
Likewise, for the 2nd fraction, since 35 × 18 = 630,
25/35 = 25 × 18/35 × 18 = 450/630
Subtract the two like fractions:
735/630 - 450/630 = 735 - 450/630 = 285/630
After reducing the fraction, the answer is 19/42

MathStep (Works offline)

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