Subtract 7/81 from 18/28
18/28 - 7/81 is 631/1134.
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,
18/28 = 18 × 81/28 × 81 = 1458/2268 - Likewise, for the 2nd fraction, since 81 × 28 = 2268,
7/81 = 7 × 28/81 × 28 = 196/2268 - Subtract the two like fractions:
1458/2268 - 196/2268 = 1458 - 196/2268 = 1262/2268 - After reducing the fraction, the answer is 631/1134
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