Subtract 42/54 from 16/21
16/21 - 42/54 is -1/63.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 54 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 21 × 18 = 378,
16/21 = 16 × 18/21 × 18 = 288/378 - Likewise, for the 2nd fraction, since 54 × 7 = 378,
42/54 = 42 × 7/54 × 7 = 294/378 - Subtract the two like fractions:
288/378 - 294/378 = 288 - 294/378 = -6/378 - After reducing the fraction, the answer is -1/63
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