Subtract 42/81 from 81/80
1st number: 1 1/80, 2nd number: 42/81
81/80 - 42/81 is 1067/2160.
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,
81/80 = 81 × 81/80 × 81 = 6561/6480 - Likewise, for the 2nd fraction, since 81 × 80 = 6480,
42/81 = 42 × 80/81 × 80 = 3360/6480 - Subtract the two like fractions:
6561/6480 - 3360/6480 = 6561 - 3360/6480 = 3201/6480 - After reducing the fraction, the answer is 1067/2160
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