Subtract 21/42 from 16/63
16/63 - 21/42 is -31/126.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 63 and 42 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 63 × 2 = 126,
16/63 = 16 × 2/63 × 2 = 32/126 - Likewise, for the 2nd fraction, since 42 × 3 = 126,
21/42 = 21 × 3/42 × 3 = 63/126 - Subtract the two like fractions:
32/126 - 63/126 = 32 - 63/126 = -31/126
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