Subtract 21/18 from 18/20
1st number: 18/20, 2nd number: 1 3/18
18/20 - 21/18 is -4/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 18 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 20 × 9 = 180,
18/20 = 18 × 9/20 × 9 = 162/180 - Likewise, for the 2nd fraction, since 18 × 10 = 180,
21/18 = 21 × 10/18 × 10 = 210/180 - Subtract the two like fractions:
162/180 - 210/180 = 162 - 210/180 = -48/180 - After reducing the fraction, the answer is -4/15
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