Subtract 15/80 from 8/81
8/81 - 15/80 is -115/1296.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 80 is 6480
Next, find the equivalent fraction of both fractional numbers with denominator 6480 - For the 1st fraction, since 81 × 80 = 6480,
8/81 = 8 × 80/81 × 80 = 640/6480 - Likewise, for the 2nd fraction, since 80 × 81 = 6480,
15/80 = 15 × 81/80 × 81 = 1215/6480 - Subtract the two like fractions:
640/6480 - 1215/6480 = 640 - 1215/6480 = -575/6480 - After reducing the fraction, the answer is -115/1296
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