Subtract 42/10 from 90/24, Solve 3 18/24

Subtract 42/10 from 90/24

1^st number: 3 18/24, 2^nd number: 4 2/10

90/24 - 42/10 is -9/20.

Find the least common denominator or LCM of the two denominators:
LCM of 24 and 10 is 120

Next, find the equivalent fraction of both fractional numbers with denominator 120
For the 1st fraction, since 24 × 5 = 120,
90/24 = 90 × 5/24 × 5 = 450/120
Likewise, for the 2nd fraction, since 10 × 12 = 120,
42/10 = 42 × 12/10 × 12 = 504/120
Subtract the two like fractions:
450/120 - 504/120 = 450 - 504/120 = -54/120
After reducing the fraction, the answer is -9/20

MathStep (Works offline)

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