Subtract 5/81 from 25/20, Solve 1 5/20

Subtract 5/81 from 25/20

1^st number: 1 5/20, 2^nd number: 5/81

25/20 - 5/81 is 385/324.

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,
25/20 = 25 × 81/20 × 81 = 2025/1620
Likewise, for the 2nd fraction, since 81 × 20 = 1620,
5/81 = 5 × 20/81 × 20 = 100/1620
Subtract the two like fractions:
2025/1620 - 100/1620 = 2025 - 100/1620 = 1925/1620
After reducing the fraction, the answer is 385/324
In mixed form: 161/324

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