Subtract 21/36 from 9/20
9/20 - 21/36 is -2/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 36 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 20 × 9 = 180,
9/20 = 9 × 9/20 × 9 = 81/180 - Likewise, for the 2nd fraction, since 36 × 5 = 180,
21/36 = 21 × 5/36 × 5 = 105/180 - Subtract the two like fractions:
81/180 - 105/180 = 81 - 105/180 = -24/180 - After reducing the fraction, the answer is -2/15
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