Subtract 42/12 from 21/27
1st number: 21/27, 2nd number: 3 6/12
21/27 - 42/12 is -49/18.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 27 and 12 is 108
Next, find the equivalent fraction of both fractional numbers with denominator 108 - For the 1st fraction, since 27 × 4 = 108,
21/27 = 21 × 4/27 × 4 = 84/108 - Likewise, for the 2nd fraction, since 12 × 9 = 108,
42/12 = 42 × 9/12 × 9 = 378/108 - Subtract the two like fractions:
84/108 - 378/108 = 84 - 378/108 = -294/108 - After reducing the fraction, the answer is -49/18
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