Subtract 4/5 from 21/28
21/28 - 4/5 is -1/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 5 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 28 × 5 = 140,
21/28 = 21 × 5/28 × 5 = 105/140 - Likewise, for the 2nd fraction, since 5 × 28 = 140,
4/5 = 4 × 28/5 × 28 = 112/140 - Subtract the two like fractions:
105/140 - 112/140 = 105 - 112/140 = -7/140 - After reducing the fraction, the answer is -1/20
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