Subtract 16/54 from 81/21, Solve 3 18/21

Subtract 16/54 from 81/21

1^st number: 3 18/21, 2^nd number: 16/54

81/21 - 16/54 is 673/189.

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,
81/21 = 81 × 18/21 × 18 = 1458/378
Likewise, for the 2nd fraction, since 54 × 7 = 378,
16/54 = 16 × 7/54 × 7 = 112/378
Subtract the two like fractions:
1458/378 - 112/378 = 1458 - 112/378 = 1346/378
After reducing the fraction, the answer is 673/189
In mixed form: 3106/189

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