Subtract 18/54 from 21/12
1st number: 1 9/12, 2nd number: 18/54
21/12 - 18/54 is 17/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 54 is 108
Next, find the equivalent fraction of both fractional numbers with denominator 108 - For the 1st fraction, since 12 × 9 = 108,
21/12 = 21 × 9/12 × 9 = 189/108 - Likewise, for the 2nd fraction, since 54 × 2 = 108,
18/54 = 18 × 2/54 × 2 = 36/108 - Subtract the two like fractions:
189/108 - 36/108 = 189 - 36/108 = 153/108 - After reducing the fraction, the answer is 17/12
- In mixed form: 15/12
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