Subtract 42/15 from 18/8
1st number: 2 2/8, 2nd number: 2 12/15
18/8 - 42/15 is -11/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 15 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 8 × 15 = 120,
18/8 = 18 × 15/8 × 15 = 270/120 - Likewise, for the 2nd fraction, since 15 × 8 = 120,
42/15 = 42 × 8/15 × 8 = 336/120 - Subtract the two like fractions:
270/120 - 336/120 = 270 - 336/120 = -66/120 - After reducing the fraction, the answer is -11/20
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 36/8-42/15 18/8-84/15 18/16-42/15 18/8-42/30 54/8-42/15 18/24-42/15 18/8-42/45 90/8-42/15 18/40-42/15 18/8-42/75 18/56-42/15