Subtract 20/16 from 15/42
1st number: 15/42, 2nd number: 1 4/16
15/42 - 20/16 is -25/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 16 is 336
Next, find the equivalent fraction of both fractional numbers with denominator 336 - For the 1st fraction, since 42 × 8 = 336,
15/42 = 15 × 8/42 × 8 = 120/336 - Likewise, for the 2nd fraction, since 16 × 21 = 336,
20/16 = 20 × 21/16 × 21 = 420/336 - Subtract the two like fractions:
120/336 - 420/336 = 120 - 420/336 = -300/336 - After reducing the fraction, the answer is -25/28
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 30/42-20/16 15/42-40/16 15/84-20/16 15/42-20/32 45/42-20/16 15/42-60/16 15/42-20/48 75/42-20/16 15/42-20/80