Subtract 63/81 from 45/80, Solve 45/80

Subtract 63/81 from 45/80

45/80 - 63/81 is -31/144.

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,
45/80 = 45 × 81/80 × 81 = 3645/6480
Likewise, for the 2nd fraction, since 81 × 80 = 6480,
63/81 = 63 × 80/81 × 80 = 5040/6480
Subtract the two like fractions:
3645/6480 - 5040/6480 = 3645 - 5040/6480 = -1395/6480
After reducing the fraction, the answer is -31/144

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