Subtract 70/21 from 7/54, Solve 7/54

Subtract 70/21 from 7/54

1^st number: 7/54, 2^nd number: 3 7/21

7/54 - 70/21 is -173/54.

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,
7/54 = 7 × 7/54 × 7 = 49/378
Likewise, for the 2nd fraction, since 21 × 18 = 378,
70/21 = 70 × 18/21 × 18 = 1260/378
Subtract the two like fractions:
49/378 - 1260/378 = 49 - 1260/378 = -1211/378
After reducing the fraction, the answer is -173/54

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