Subtract 21/54 from 12/7, Solve 1 5/7

Subtract 21/54 from 12/7

1^st number: 1 5/7, 2^nd number: 21/54

12/7 - 21/54 is 167/126.

Find the least common denominator or LCM of the two denominators:
LCM of 7 and 54 is 378

Next, find the equivalent fraction of both fractional numbers with denominator 378
For the 1st fraction, since 7 × 54 = 378,
12/7 = 12 × 54/7 × 54 = 648/378
Likewise, for the 2nd fraction, since 54 × 7 = 378,
21/54 = 21 × 7/54 × 7 = 147/378
Subtract the two like fractions:
648/378 - 147/378 = 648 - 147/378 = 501/378
After reducing the fraction, the answer is 167/126
In mixed form: 141/126

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