Subtract 81/21 from 7/36
1st number: 7/36, 2nd number: 3 18/21
7/36 - 81/21 is -923/252.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 21 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 36 × 7 = 252,
7/36 = 7 × 7/36 × 7 = 49/252 - Likewise, for the 2nd fraction, since 21 × 12 = 252,
81/21 = 81 × 12/21 × 12 = 972/252 - Subtract the two like fractions:
49/252 - 972/252 = 49 - 972/252 = -923/252
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