Subtract 70/81 from 20/28
20/28 - 70/81 is -85/567.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 81 is 2268
Next, find the equivalent fraction of both fractional numbers with denominator 2268 - For the 1st fraction, since 28 × 81 = 2268,
20/28 = 20 × 81/28 × 81 = 1620/2268 - Likewise, for the 2nd fraction, since 81 × 28 = 2268,
70/81 = 70 × 28/81 × 28 = 1960/2268 - Subtract the two like fractions:
1620/2268 - 1960/2268 = 1620 - 1960/2268 = -340/2268 - After reducing the fraction, the answer is -85/567
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