Subtract 42/28 from 16/21
1st number: 16/21, 2nd number: 1 14/28
16/21 - 42/28 is -31/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 28 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
16/21 = 16 × 4/21 × 4 = 64/84 - Likewise, for the 2nd fraction, since 28 × 3 = 84,
42/28 = 42 × 3/28 × 3 = 126/84 - Subtract the two like fractions:
64/84 - 126/84 = 64 - 126/84 = -62/84 - After reducing the fraction, the answer is -31/42
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