Subtract 21/15 from 27/42
1st number: 27/42, 2nd number: 1 6/15
27/42 - 21/15 is -53/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 15 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 42 × 5 = 210,
27/42 = 27 × 5/42 × 5 = 135/210 - Likewise, for the 2nd fraction, since 15 × 14 = 210,
21/15 = 21 × 14/15 × 14 = 294/210 - Subtract the two like fractions:
135/210 - 294/210 = 135 - 294/210 = -159/210 - After reducing the fraction, the answer is -53/70
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