Subtract 21/24 from 30/54, Solve 30/54

Subtract 21/24 from 30/54

30/54 - 21/24 is -23/72.

Find the least common denominator or LCM of the two denominators:
LCM of 54 and 24 is 216

Next, find the equivalent fraction of both fractional numbers with denominator 216
For the 1st fraction, since 54 × 4 = 216,
30/54 = 30 × 4/54 × 4 = 120/216
Likewise, for the 2nd fraction, since 24 × 9 = 216,
21/24 = 21 × 9/24 × 9 = 189/216
Subtract the two like fractions:
120/216 - 189/216 = 120 - 189/216 = -69/216
After reducing the fraction, the answer is -23/72

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