Subtract 45/81 from 1/28, Solve 1/28

Subtract 45/81 from 1/28

1/28 - 45/81 is -131/252.

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,
1/28 = 1 × 81/28 × 81 = 81/2268
Likewise, for the 2nd fraction, since 81 × 28 = 2268,
45/81 = 45 × 28/81 × 28 = 1260/2268
Subtract the two like fractions:
81/2268 - 1260/2268 = 81 - 1260/2268 = -1179/2268
After reducing the fraction, the answer is -131/252

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