Subtract 80/54 from 9/21, Solve 9/21

Subtract 80/54 from 9/21

1^st number: 9/21, 2^nd number: 1 26/54

9/21 - 80/54 is -199/189.

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,
9/21 = 9 × 18/21 × 18 = 162/378
Likewise, for the 2nd fraction, since 54 × 7 = 378,
80/54 = 80 × 7/54 × 7 = 560/378
Subtract the two like fractions:
162/378 - 560/378 = 162 - 560/378 = -398/378
After reducing the fraction, the answer is -199/189

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