Subtract 18/84 from 15/90
15/90 - 18/84 is -1/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 84 is 1260
Next, find the equivalent fraction of both fractional numbers with denominator 1260 - For the 1st fraction, since 90 × 14 = 1260,
15/90 = 15 × 14/90 × 14 = 210/1260 - Likewise, for the 2nd fraction, since 84 × 15 = 1260,
18/84 = 18 × 15/84 × 15 = 270/1260 - Subtract the two like fractions:
210/1260 - 270/1260 = 210 - 270/1260 = -60/1260 - After reducing the fraction, the answer is -1/21
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