Subtract 72/90 from 4/84
4/84 - 72/90 is -79/105.
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,
4/84 = 4 × 15/84 × 15 = 60/1260 - Likewise, for the 2nd fraction, since 90 × 14 = 1260,
72/90 = 72 × 14/90 × 14 = 1008/1260 - Subtract the two like fractions:
60/1260 - 1008/1260 = 60 - 1008/1260 = -948/1260 - After reducing the fraction, the answer is -79/105
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