Subtract 15/18 from 20/90
20/90 - 15/18 is -11/18.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 18 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 90 × 1 = 90,
20/90 = 20 × 1/90 × 1 = 20/90 - Likewise, for the 2nd fraction, since 18 × 5 = 90,
15/18 = 15 × 5/18 × 5 = 75/90 - Subtract the two like fractions:
20/90 - 75/90 = 20 - 75/90 = -55/90 - After reducing the fraction, the answer is -11/18
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