Subtract 75/81 from 28/70
28/70 - 75/81 is -71/135.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 81 is 5670
Next, find the equivalent fraction of both fractional numbers with denominator 5670 - For the 1st fraction, since 70 × 81 = 5670,
28/70 = 28 × 81/70 × 81 = 2268/5670 - Likewise, for the 2nd fraction, since 81 × 70 = 5670,
75/81 = 75 × 70/81 × 70 = 5250/5670 - Subtract the two like fractions:
2268/5670 - 5250/5670 = 2268 - 5250/5670 = -2982/5670 - After reducing the fraction, the answer is -71/135
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