Subtract 21/8 from 7/28
1st number: 7/28, 2nd number: 2 5/8
7/28 - 21/8 is -19/8.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 8 is 56
Next, find the equivalent fraction of both fractional numbers with denominator 56 - For the 1st fraction, since 28 × 2 = 56,
7/28 = 7 × 2/28 × 2 = 14/56 - Likewise, for the 2nd fraction, since 8 × 7 = 56,
21/8 = 21 × 7/8 × 7 = 147/56 - Subtract the two like fractions:
14/56 - 147/56 = 14 - 147/56 = -133/56 - After reducing the fraction, the answer is -19/8
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