Subtract 21/7 from 1/8
1st number: 1/8, 2nd number: 3 0/7
1/8 - 21/7 is -23/8.
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,
1/8 = 1 × 7/8 × 7 = 7/56 - Likewise, for the 2nd fraction, since 7 × 8 = 56,
21/7 = 21 × 8/7 × 8 = 168/56 - Subtract the two like fractions:
7/56 - 168/56 = 7 - 168/56 = -161/56 - After reducing the fraction, the answer is -23/8
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