Subtract 75/90 from 20/84
20/84 - 75/90 is -25/42.
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,
20/84 = 20 × 15/84 × 15 = 300/1260 - Likewise, for the 2nd fraction, since 90 × 14 = 1260,
75/90 = 75 × 14/90 × 14 = 1050/1260 - Subtract the two like fractions:
300/1260 - 1050/1260 = 300 - 1050/1260 = -750/1260 - After reducing the fraction, the answer is -25/42
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