Subtract 90/84 from 72/90
1st number: 72/90, 2nd number: 1 6/84
72/90 - 90/84 is -19/70.
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,
72/90 = 72 × 14/90 × 14 = 1008/1260 - Likewise, for the 2nd fraction, since 84 × 15 = 1260,
90/84 = 90 × 15/84 × 15 = 1350/1260 - Subtract the two like fractions:
1008/1260 - 1350/1260 = 1008 - 1350/1260 = -342/1260 - After reducing the fraction, the answer is -19/70
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