Subtract 9/21 from 42/54, Solve 42/54

Subtract 9/21 from 42/54

42/54 - 9/21 is 22/63.

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,
42/54 = 42 × 7/54 × 7 = 294/378
Likewise, for the 2nd fraction, since 21 × 18 = 378,
9/21 = 9 × 18/21 × 18 = 162/378
Subtract the two like fractions:
294/378 - 162/378 = 294 - 162/378 = 132/378
After reducing the fraction, the answer is 22/63

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