Subtract 9/81 from 1/80, Solve 1/80

Subtract 9/81 from 1/80

1/80 - 9/81 is -71/720.

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,
1/80 = 1 × 81/80 × 81 = 81/6480
Likewise, for the 2nd fraction, since 81 × 80 = 6480,
9/81 = 9 × 80/81 × 80 = 720/6480
Subtract the two like fractions:
81/6480 - 720/6480 = 81 - 720/6480 = -639/6480
After reducing the fraction, the answer is -71/720

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