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