Subtract 28/7 from 21/8
1st number: 2 5/8, 2nd number: 4 0/7
21/8 - 28/7 is -11/8.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 7 is 56
Next, find the equivalent fraction of both fractional numbers with denominator 56 - For the 1st fraction, since 8 × 7 = 56,
21/8 = 21 × 7/8 × 7 = 147/56 - Likewise, for the 2nd fraction, since 7 × 8 = 56,
28/7 = 28 × 8/7 × 8 = 224/56 - Subtract the two like fractions:
147/56 - 224/56 = 147 - 224/56 = -77/56 - After reducing the fraction, the answer is -11/8
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