Subtract 21/64 from 8/42
8/42 - 21/64 is -185/1344.
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,
8/42 = 8 × 32/42 × 32 = 256/1344 - Likewise, for the 2nd fraction, since 64 × 21 = 1344,
21/64 = 21 × 21/64 × 21 = 441/1344 - Subtract the two like fractions:
256/1344 - 441/1344 = 256 - 441/1344 = -185/1344
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