Subtract 21/81 from 2/28
2/28 - 21/81 is -71/378.
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,
2/28 = 2 × 81/28 × 81 = 162/2268 - Likewise, for the 2nd fraction, since 81 × 28 = 2268,
21/81 = 21 × 28/81 × 28 = 588/2268 - Subtract the two like fractions:
162/2268 - 588/2268 = 162 - 588/2268 = -426/2268 - After reducing the fraction, the answer is -71/378
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