Subtract 30/81 from 28/80
28/80 - 30/81 is -11/540.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 81 is 6480
Next, find the equivalent fraction of both fractional numbers with denominator 6480 - For the 1st fraction, since 80 × 81 = 6480,
28/80 = 28 × 81/80 × 81 = 2268/6480 - Likewise, for the 2nd fraction, since 81 × 80 = 6480,
30/81 = 30 × 80/81 × 80 = 2400/6480 - Subtract the two like fractions:
2268/6480 - 2400/6480 = 2268 - 2400/6480 = -132/6480 - After reducing the fraction, the answer is -11/540
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