Subtract 3/81 from 12/20, Solve 12/20

Subtract 3/81 from 12/20

12/20 - 3/81 is 76/135.

Find the least common denominator or LCM of the two denominators:
LCM of 20 and 81 is 1620

Next, find the equivalent fraction of both fractional numbers with denominator 1620
For the 1st fraction, since 20 × 81 = 1620,
12/20 = 12 × 81/20 × 81 = 972/1620
Likewise, for the 2nd fraction, since 81 × 20 = 1620,
3/81 = 3 × 20/81 × 20 = 60/1620
Subtract the two like fractions:
972/1620 - 60/1620 = 972 - 60/1620 = 912/1620
After reducing the fraction, the answer is 76/135

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