Subtract 56/36 from 81/21
1st number: 3 18/21, 2nd number: 1 20/36
81/21 - 56/36 is 145/63.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 36 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 21 × 12 = 252,
81/21 = 81 × 12/21 × 12 = 972/252 - Likewise, for the 2nd fraction, since 36 × 7 = 252,
56/36 = 56 × 7/36 × 7 = 392/252 - Subtract the two like fractions:
972/252 - 392/252 = 972 - 392/252 = 580/252 - After reducing the fraction, the answer is 145/63
- In mixed form: 219/63
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