Subtract 60/90 from 81/70, Solve 1 11/70

Subtract 60/90 from 81/70

1^st number: 1 11/70, 2^nd number: 60/90

81/70 - 60/90 is 103/210.

Find the least common denominator or LCM of the two denominators:
LCM of 70 and 90 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 70 × 9 = 630,
81/70 = 81 × 9/70 × 9 = 729/630
Likewise, for the 2nd fraction, since 90 × 7 = 630,
60/90 = 60 × 7/90 × 7 = 420/630
Subtract the two like fractions:
729/630 - 420/630 = 729 - 420/630 = 309/630
After reducing the fraction, the answer is 103/210

MathStep (Works offline)

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