Subtract 3/54 from 21/7, Solve 3 0/7

Subtract 3/54 from 21/7

1^st number: 3 0/7, 2^nd number: 3/54

21/7 - 3/54 is 53/18.

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,
21/7 = 21 × 54/7 × 54 = 1134/378
Likewise, for the 2nd fraction, since 54 × 7 = 378,
3/54 = 3 × 7/54 × 7 = 21/378
Subtract the two like fractions:
1134/378 - 21/378 = 1134 - 21/378 = 1113/378
After reducing the fraction, the answer is 53/18
In mixed form: 217/18

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