Subtract 8/7 from 21/36
1st number: 21/36, 2nd number: 1 1/7
21/36 - 8/7 is -47/84.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 7 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 36 × 7 = 252,
21/36 = 21 × 7/36 × 7 = 147/252 - Likewise, for the 2nd fraction, since 7 × 36 = 252,
8/7 = 8 × 36/7 × 36 = 288/252 - Subtract the two like fractions:
147/252 - 288/252 = 147 - 288/252 = -141/252 - After reducing the fraction, the answer is -47/84
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