Subtract 1/48 from 21/42
21/42 - 1/48 is 23/48.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 48 is 336
Next, find the equivalent fraction of both fractional numbers with denominator 336 - For the 1st fraction, since 42 × 8 = 336,
21/42 = 21 × 8/42 × 8 = 168/336 - Likewise, for the 2nd fraction, since 48 × 7 = 336,
1/48 = 1 × 7/48 × 7 = 7/336 - Subtract the two like fractions:
168/336 - 7/336 = 168 - 7/336 = 161/336 - After reducing the fraction, the answer is 23/48
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 21/42-2/48 21/84-1/48 21/42-1/96 63/42-1/48 21/42-3/48 21/42-5/48 21/42-7/48