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