Subtract 21/15 from 20/36
1st number: 20/36, 2nd number: 1 6/15
20/36 - 21/15 is -38/45.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 15 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 36 × 5 = 180,
20/36 = 20 × 5/36 × 5 = 100/180 - Likewise, for the 2nd fraction, since 15 × 12 = 180,
21/15 = 21 × 12/15 × 12 = 252/180 - Subtract the two like fractions:
100/180 - 252/180 = 100 - 252/180 = -152/180 - After reducing the fraction, the answer is -38/45
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