Subtract 21/36 from 15/30
15/30 - 21/36 is -1/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 36 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 30 × 6 = 180,
15/30 = 15 × 6/30 × 6 = 90/180 - Likewise, for the 2nd fraction, since 36 × 5 = 180,
21/36 = 21 × 5/36 × 5 = 105/180 - Subtract the two like fractions:
90/180 - 105/180 = 90 - 105/180 = -15/180 - After reducing the fraction, the answer is -1/12
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