Subtract 49/64 from 21/42
21/42 - 49/64 is -17/64.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 64 is 1344
Next, find the equivalent fraction of both fractional numbers with denominator 1344 - For the 1st fraction, since 42 × 32 = 1344,
21/42 = 21 × 32/42 × 32 = 672/1344 - Likewise, for the 2nd fraction, since 64 × 21 = 1344,
49/64 = 49 × 21/64 × 21 = 1029/1344 - Subtract the two like fractions:
672/1344 - 1029/1344 = 672 - 1029/1344 = -357/1344 - After reducing the fraction, the answer is -17/64
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