Subtract 54/10 from 18/84, Solve 18/84

Subtract 54/10 from 18/84

1^st number: 18/84, 2^nd number: 5 4/10

18/84 - 54/10 is -363/70.

Find the least common denominator or LCM of the two denominators:
LCM of 84 and 10 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 84 × 5 = 420,
18/84 = 18 × 5/84 × 5 = 90/420
Likewise, for the 2nd fraction, since 10 × 42 = 420,
54/10 = 54 × 42/10 × 42 = 2268/420
Subtract the two like fractions:
90/420 - 2268/420 = 90 - 2268/420 = -2178/420
After reducing the fraction, the answer is -363/70

MathStep (Works offline)

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