Subtract 1/21 from 54/36, Solve 1 18/36

Subtract 1/21 from 54/36

1^st number: 1 18/36, 2^nd number: 1/21

54/36 - 1/21 is 61/42.

Find the least common denominator or LCM of the two denominators:
LCM of 36 and 21 is 252

Next, find the equivalent fraction of both fractional numbers with denominator 252
For the 1st fraction, since 36 × 7 = 252,
54/36 = 54 × 7/36 × 7 = 378/252
Likewise, for the 2nd fraction, since 21 × 12 = 252,
1/21 = 1 × 12/21 × 12 = 12/252
Subtract the two like fractions:
378/252 - 12/252 = 378 - 12/252 = 366/252
After reducing the fraction, the answer is 61/42
In mixed form: 119/42

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