Subtract 1/42 from 15/45, Solve 15/45

Subtract 1/42 from 15/45

15/45 - 1/42 is 13/42.

Find the least common denominator or LCM of the two denominators:
LCM of 45 and 42 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 45 × 14 = 630,
15/45 = 15 × 14/45 × 14 = 210/630
Likewise, for the 2nd fraction, since 42 × 15 = 630,
1/42 = 1 × 15/42 × 15 = 15/630
Subtract the two like fractions:
210/630 - 15/630 = 210 - 15/630 = 195/630
After reducing the fraction, the answer is 13/42

MathStep (Works offline)

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