Subtract 21/36 from 30/54, Solve 30/54

Subtract 21/36 from 30/54

30/54 - 21/36 is -1/36.

Find the least common denominator or LCM of the two denominators:
LCM of 54 and 36 is 108

Next, find the equivalent fraction of both fractional numbers with denominator 108
For the 1st fraction, since 54 × 2 = 108,
30/54 = 30 × 2/54 × 2 = 60/108
Likewise, for the 2nd fraction, since 36 × 3 = 108,
21/36 = 21 × 3/36 × 3 = 63/108
Subtract the two like fractions:
60/108 - 63/108 = 60 - 63/108 = -3/108
After reducing the fraction, the answer is -1/36

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