Subtract 80/21 from 50/54, Solve 50/54

Subtract 80/21 from 50/54

1^st number: 50/54, 2^nd number: 3 17/21

50/54 - 80/21 is -545/189.

Find the least common denominator or LCM of the two denominators:
LCM of 54 and 21 is 378

Next, find the equivalent fraction of both fractional numbers with denominator 378
For the 1st fraction, since 54 × 7 = 378,
50/54 = 50 × 7/54 × 7 = 350/378
Likewise, for the 2nd fraction, since 21 × 18 = 378,
80/21 = 80 × 18/21 × 18 = 1440/378
Subtract the two like fractions:
350/378 - 1440/378 = 350 - 1440/378 = -1090/378
After reducing the fraction, the answer is -545/189

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