Subtract 18/12 from 21/54
1st number: 21/54, 2nd number: 1 6/12
21/54 - 18/12 is -10/9.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 54 and 12 is 108
Next, find the equivalent fraction of both fractional numbers with denominator 108 - For the 1st fraction, since 54 × 2 = 108,
21/54 = 21 × 2/54 × 2 = 42/108 - Likewise, for the 2nd fraction, since 12 × 9 = 108,
18/12 = 18 × 9/12 × 9 = 162/108 - Subtract the two like fractions:
42/108 - 162/108 = 42 - 162/108 = -120/108 - After reducing the fraction, the answer is -10/9
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