Subtract 21/84 from 7/90
7/90 - 21/84 is -31/180.
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,
7/90 = 7 × 14/90 × 14 = 98/1260 - Likewise, for the 2nd fraction, since 84 × 15 = 1260,
21/84 = 21 × 15/84 × 15 = 315/1260 - Subtract the two like fractions:
98/1260 - 315/1260 = 98 - 315/1260 = -217/1260 - After reducing the fraction, the answer is -31/180
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