Subtract 42/80 from 70/81
70/81 - 42/80 is 1099/3240.
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,
70/81 = 70 × 80/81 × 80 = 5600/6480 - Likewise, for the 2nd fraction, since 80 × 81 = 6480,
42/80 = 42 × 81/80 × 81 = 3402/6480 - Subtract the two like fractions:
5600/6480 - 3402/6480 = 5600 - 3402/6480 = 2198/6480 - After reducing the fraction, the answer is 1099/3240
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