Subtract 7/80 from 21/84
21/84 - 7/80 is 13/80.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 80 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 84 × 20 = 1680,
21/84 = 21 × 20/84 × 20 = 420/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
7/80 = 7 × 21/80 × 21 = 147/1680 - Subtract the two like fractions:
420/1680 - 147/1680 = 420 - 147/1680 = 273/1680 - After reducing the fraction, the answer is 13/80
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/84-7/80 21/84-14/80 63/84-7/80 21/84-21/80 21/84-35/80 21/84-49/80