Subtract 15/90 from 18/20
18/20 - 15/90 is 11/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 90 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 90 × 2 = 180,
15/90 = 15 × 2/90 × 2 = 30/180 - Subtract the two like fractions:
162/180 - 30/180 = 162 - 30/180 = 132/180 - After reducing the fraction, the answer is 11/15
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