Subtract 80/81 from 42/80
42/80 - 80/81 is -1499/3240.
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,
42/80 = 42 × 81/80 × 81 = 3402/6480 - Likewise, for the 2nd fraction, since 81 × 80 = 6480,
80/81 = 80 × 80/81 × 80 = 6400/6480 - Subtract the two like fractions:
3402/6480 - 6400/6480 = 3402 - 6400/6480 = -2998/6480 - After reducing the fraction, the answer is -1499/3240
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