Subtract 9/54 from 27/21, Solve 1 6/21

Subtract 9/54 from 27/21

1^st number: 1 6/21, 2^nd number: 9/54

27/21 - 9/54 is 47/42.

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,
27/21 = 27 × 18/21 × 18 = 486/378
Likewise, for the 2nd fraction, since 54 × 7 = 378,
9/54 = 9 × 7/54 × 7 = 63/378
Subtract the two like fractions:
486/378 - 63/378 = 486 - 63/378 = 423/378
After reducing the fraction, the answer is 47/42
In mixed form: 15/42

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