Subtract 42/90 from 7/84
7/84 - 42/90 is -23/60.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 90 is 1260
Next, find the equivalent fraction of both fractional numbers with denominator 1260 - For the 1st fraction, since 84 × 15 = 1260,
7/84 = 7 × 15/84 × 15 = 105/1260 - Likewise, for the 2nd fraction, since 90 × 14 = 1260,
42/90 = 42 × 14/90 × 14 = 588/1260 - Subtract the two like fractions:
105/1260 - 588/1260 = 105 - 588/1260 = -483/1260 - After reducing the fraction, the answer is -23/60
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