Subtract 5/54 from 84/21, Solve 4 0/21

Subtract 5/54 from 84/21

1^st number: 4 0/21, 2^nd number: 5/54

84/21 - 5/54 is 211/54.

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,
84/21 = 84 × 18/21 × 18 = 1512/378
Likewise, for the 2nd fraction, since 54 × 7 = 378,
5/54 = 5 × 7/54 × 7 = 35/378
Subtract the two like fractions:
1512/378 - 35/378 = 1512 - 35/378 = 1477/378
After reducing the fraction, the answer is 211/54
In mixed form: 349/54

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