Subtract 24/81 from 7/20, Solve 7/20

Subtract 24/81 from 7/20

7/20 - 24/81 is 29/540.

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,
7/20 = 7 × 81/20 × 81 = 567/1620
Likewise, for the 2nd fraction, since 81 × 20 = 1620,
24/81 = 24 × 20/81 × 20 = 480/1620
Subtract the two like fractions:
567/1620 - 480/1620 = 567 - 480/1620 = 87/1620
After reducing the fraction, the answer is 29/540

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