Subtract 15/16 from 21/42
21/42 - 15/16 is -7/16.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 16 is 336
Next, find the equivalent fraction of both fractional numbers with denominator 336 - For the 1st fraction, since 42 × 8 = 336,
21/42 = 21 × 8/42 × 8 = 168/336 - Likewise, for the 2nd fraction, since 16 × 21 = 336,
15/16 = 15 × 21/16 × 21 = 315/336 - Subtract the two like fractions:
168/336 - 315/336 = 168 - 315/336 = -147/336 - After reducing the fraction, the answer is -7/16
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