Add 21/5 and 5/81, Solve 4 1/5 + 5/81 as a fraction

Add 21/5 and 5/81

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

21/5 + 5/81 is 1726/405.

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,
21/5 = 21 × 81/5 × 81 = 1701/405
Likewise, for the 2nd fraction, since 81 × 5 = 405,
5/81 = 5 × 5/81 × 5 = 25/405
Add the two like fractions:
1701/405 + 25/405 = 1701 + 25/405 = 1726/405
So, 21/5 + 5/81 = 1726/405
In mixed form: 4106/405

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