Subtract 21/8 from 28/21
1st number: 1 7/21, 2nd number: 2 5/8
28/21 - 21/8 is -31/24.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 8 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 21 × 8 = 168,
28/21 = 28 × 8/21 × 8 = 224/168 - Likewise, for the 2nd fraction, since 8 × 21 = 168,
21/8 = 21 × 21/8 × 21 = 441/168 - Subtract the two like fractions:
224/168 - 441/168 = 224 - 441/168 = -217/168 - After reducing the fraction, the answer is -31/24
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