Subtract 16/54 from 15/21
15/21 - 16/54 is 79/189.
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,
15/21 = 15 × 18/21 × 18 = 270/378 - Likewise, for the 2nd fraction, since 54 × 7 = 378,
16/54 = 16 × 7/54 × 7 = 112/378 - Subtract the two like fractions:
270/378 - 112/378 = 270 - 112/378 = 158/378 - After reducing the fraction, the answer is 79/189
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