Subtract 30/84 from 21/90
21/90 - 30/84 is -13/105.
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,
21/90 = 21 × 14/90 × 14 = 294/1260 - Likewise, for the 2nd fraction, since 84 × 15 = 1260,
30/84 = 30 × 15/84 × 15 = 450/1260 - Subtract the two like fractions:
294/1260 - 450/1260 = 294 - 450/1260 = -156/1260 - After reducing the fraction, the answer is -13/105
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