Subtract 21/54 from 42/12
1st number: 3 6/12, 2nd number: 21/54
42/12 - 21/54 is 28/9.
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,
42/12 = 42 × 9/12 × 9 = 378/108 - Likewise, for the 2nd fraction, since 54 × 2 = 108,
21/54 = 21 × 2/54 × 2 = 42/108 - Subtract the two like fractions:
378/108 - 42/108 = 378 - 42/108 = 336/108 - After reducing the fraction, the answer is 28/9
- In mixed form: 31/9
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