Subtract 80/21 from 21/28
1st number: 21/28, 2nd number: 3 17/21
21/28 - 80/21 is -257/84.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 28 × 3 = 84,
21/28 = 21 × 3/28 × 3 = 63/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
80/21 = 80 × 4/21 × 4 = 320/84 - Subtract the two like fractions:
63/84 - 320/84 = 63 - 320/84 = -257/84
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