Subtract 21/15 from 27/30
1st number: 27/30, 2nd number: 1 6/15
27/30 - 21/15 is -1/2.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 15 is 30
Next, find the equivalent fraction of both fractional numbers with denominator 30 - For the 1st fraction, since 30 × 1 = 30,
27/30 = 27 × 1/30 × 1 = 27/30 - Likewise, for the 2nd fraction, since 15 × 2 = 30,
21/15 = 21 × 2/15 × 2 = 42/30 - Subtract the two like fractions:
27/30 - 42/30 = 27 - 42/30 = -15/30 - After reducing the fraction, the answer is -1/2
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