Subtract 72/7 from 21/36
1st number: 21/36, 2nd number: 10 2/7
21/36 - 72/7 is -815/84.
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,
72/7 = 72 × 36/7 × 36 = 2592/252 - Subtract the two like fractions:
147/252 - 2592/252 = 147 - 2592/252 = -2445/252 - After reducing the fraction, the answer is -815/84
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