Subtract 5/21 from 70/54, Solve 1 16/54

Subtract 5/21 from 70/54

1^st number: 1 16/54, 2^nd number: 5/21

70/54 - 5/21 is 200/189.

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,
70/54 = 70 × 7/54 × 7 = 490/378
Likewise, for the 2nd fraction, since 21 × 18 = 378,
5/21 = 5 × 18/21 × 18 = 90/378
Subtract the two like fractions:
490/378 - 90/378 = 490 - 90/378 = 400/378
After reducing the fraction, the answer is 200/189
In mixed form: 111/189

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