Subtract 42/21 from 27/15
1st number: 1 12/15, 2nd number: 2 0/21
27/15 - 42/21 is -1/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 15 × 7 = 105,
27/15 = 27 × 7/15 × 7 = 189/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
42/21 = 42 × 5/21 × 5 = 210/105 - Subtract the two like fractions:
189/105 - 210/105 = 189 - 210/105 = -21/105 - After reducing the fraction, the answer is -1/5
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