Subtract 3/81 from 3/80, Solve 3/80

Subtract 3/81 from 3/80

3/80 - 3/81 is 1/2160.

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,
3/80 = 3 × 81/80 × 81 = 243/6480
Likewise, for the 2nd fraction, since 81 × 80 = 6480,
3/81 = 3 × 80/81 × 80 = 240/6480
Subtract the two like fractions:
243/6480 - 240/6480 = 243 - 240/6480 = 3/6480
After reducing the fraction, the answer is 1/2160

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