Subtract 70/81 from 28/84
28/84 - 70/81 is -43/81.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 81 is 2268
Next, find the equivalent fraction of both fractional numbers with denominator 2268 - For the 1st fraction, since 84 × 27 = 2268,
28/84 = 28 × 27/84 × 27 = 756/2268 - Likewise, for the 2nd fraction, since 81 × 28 = 2268,
70/81 = 70 × 28/81 × 28 = 1960/2268 - Subtract the two like fractions:
756/2268 - 1960/2268 = 756 - 1960/2268 = -1204/2268 - After reducing the fraction, the answer is -43/81
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Related: 56/84-70/81