Subtract 90/21 from 81/64
1st number: 1 17/64, 2nd number: 4 6/21
81/64 - 90/21 is -1353/448.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 64 and 21 is 1344
Next, find the equivalent fraction of both fractional numbers with denominator 1344 - For the 1st fraction, since 64 × 21 = 1344,
81/64 = 81 × 21/64 × 21 = 1701/1344 - Likewise, for the 2nd fraction, since 21 × 64 = 1344,
90/21 = 90 × 64/21 × 64 = 5760/1344 - Subtract the two like fractions:
1701/1344 - 5760/1344 = 1701 - 5760/1344 = -4059/1344 - After reducing the fraction, the answer is -1353/448
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