Add 21/16 and 5/81, Solve 1 5/16 + 5/81 as a fraction

Add 21/16 and 5/81

1^st number: 1 5/16, 2^nd number: 5/81

21/16 + 5/81 is 1781/1296.

Find the least common denominator or LCM of the two denominators:
LCM of 16 and 81 is 1296

Next, find the equivalent fraction of both fractional numbers with denominator 1296
For the 1st fraction, since 16 × 81 = 1296,
21/16 = 21 × 81/16 × 81 = 1701/1296
Likewise, for the 2nd fraction, since 81 × 16 = 1296,
5/81 = 5 × 16/81 × 16 = 80/1296
Add the two like fractions:
1701/1296 + 80/1296 = 1701 + 80/1296 = 1781/1296
So, 21/16 + 5/81 = 1781/1296
In mixed form: 1485/1296

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