Subtract 21/8 from 45/7
1st number: 6 3/7, 2nd number: 2 5/8
45/7 - 21/8 is 213/56.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 8 is 56
Next, find the equivalent fraction of both fractional numbers with denominator 56 - For the 1st fraction, since 7 × 8 = 56,
45/7 = 45 × 8/7 × 8 = 360/56 - Likewise, for the 2nd fraction, since 8 × 7 = 56,
21/8 = 21 × 7/8 × 7 = 147/56 - Subtract the two like fractions:
360/56 - 147/56 = 360 - 147/56 = 213/56 - In mixed form: 345/56
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 90/7-21/8 45/7-42/8 45/14-21/8 45/7-21/16 45/7-63/8 45/21-21/8 45/7-21/24 45/35-21/8 45/7-21/40 45/49-21/8 45/7-21/56