Subtract 42/27 from 21/12
1st number: 1 9/12, 2nd number: 1 15/27
21/12 - 42/27 is 7/36.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 27 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 27 × 4 = 108,
42/27 = 42 × 4/27 × 4 = 168/108 - Subtract the two like fractions:
189/108 - 168/108 = 189 - 168/108 = 21/108 - After reducing the fraction, the answer is 7/36
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