Subtract 3/81 from 20/5, Solve 4 0/5

Subtract 3/81 from 20/5

1^st number: 4 0/5, 2^nd number: 3/81

20/5 - 3/81 is 107/27.

Find the least common denominator or LCM of the two denominators:
LCM of 5 and 81 is 405

Next, find the equivalent fraction of both fractional numbers with denominator 405
For the 1st fraction, since 5 × 81 = 405,
20/5 = 20 × 81/5 × 81 = 1620/405
Likewise, for the 2nd fraction, since 81 × 5 = 405,
3/81 = 3 × 5/81 × 5 = 15/405
Subtract the two like fractions:
1620/405 - 15/405 = 1620 - 15/405 = 1605/405
After reducing the fraction, the answer is 107/27
In mixed form: 326/27

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