Subtract 1/81 from 20/5, Solve 4 0/5

Subtract 1/81 from 20/5

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

20/5 - 1/81 is 323/81.

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,
1/81 = 1 × 5/81 × 5 = 5/405
Subtract the two like fractions:
1620/405 - 5/405 = 1620 - 5/405 = 1615/405
After reducing the fraction, the answer is 323/81
In mixed form: 380/81

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