Subtract 21/18 from 27/90
1st number: 27/90, 2nd number: 1 3/18
27/90 - 21/18 is -13/15.
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,
27/90 = 27 × 1/90 × 1 = 27/90 - Likewise, for the 2nd fraction, since 18 × 5 = 90,
21/18 = 21 × 5/18 × 5 = 105/90 - Subtract the two like fractions:
27/90 - 105/90 = 27 - 105/90 = -78/90 - After reducing the fraction, the answer is -13/15
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