Subtract 50/12 from 30/80, Solve 30/80

Subtract 50/12 from 30/80

1^st number: 30/80, 2^nd number: 4 2/12

30/80 - 50/12 is -91/24.

Find the least common denominator or LCM of the two denominators:
LCM of 80 and 12 is 240

Next, find the equivalent fraction of both fractional numbers with denominator 240
For the 1st fraction, since 80 × 3 = 240,
30/80 = 30 × 3/80 × 3 = 90/240
Likewise, for the 2nd fraction, since 12 × 20 = 240,
50/12 = 50 × 20/12 × 20 = 1000/240
Subtract the two like fractions:
90/240 - 1000/240 = 90 - 1000/240 = -910/240
After reducing the fraction, the answer is -91/24

MathStep (Works offline)

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