Add 21/5 and 36/81, Solve 4 1/5 + 36/81 as a fraction

Add 21/5 and 36/81

1^st number: 4 1/5, 2^nd number: 36/81

21/5 + 36/81 is 209/45.

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,
36/81 = 36 × 5/81 × 5 = 180/405
Add the two like fractions:
1701/405 + 180/405 = 1701 + 180/405 = 1881/405
1881/405 simplified gives 209/45
So, 21/5 + 36/81 = 209/45
In mixed form: 429/45

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