Subtract 8/42 from 6/40, Solve 6/40

Subtract 8/42 from 6/40

6/40 - 8/42 is -17/420.

Find the least common denominator or LCM of the two denominators:
LCM of 40 and 42 is 840

Next, find the equivalent fraction of both fractional numbers with denominator 840
For the 1st fraction, since 40 × 21 = 840,
6/40 = 6 × 21/40 × 21 = 126/840
Likewise, for the 2nd fraction, since 42 × 20 = 840,
8/42 = 8 × 20/42 × 20 = 160/840
Subtract the two like fractions:
126/840 - 160/840 = 126 - 160/840 = -34/840
After reducing the fraction, the answer is -17/420

MathStep (Works offline)

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