Subtract 21/12 from 20/54
1st number: 20/54, 2nd number: 1 9/12
20/54 - 21/12 is -149/108.
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,
20/54 = 20 × 2/54 × 2 = 40/108 - Likewise, for the 2nd fraction, since 12 × 9 = 108,
21/12 = 21 × 9/12 × 9 = 189/108 - Subtract the two like fractions:
40/108 - 189/108 = 40 - 189/108 = -149/108
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