Add 21/10 and 4/81, Solve 2 1/10 + 4/81 as a fraction

Add 21/10 and 4/81

1^st number: 2 1/10, 2^nd number: 4/81

21/10 + 4/81 is 1741/810.

Find the least common denominator or LCM of the two denominators:
LCM of 10 and 81 is 810

Next, find the equivalent fraction of both fractional numbers with denominator 810
For the 1st fraction, since 10 × 81 = 810,
21/10 = 21 × 81/10 × 81 = 1701/810
Likewise, for the 2nd fraction, since 81 × 10 = 810,
4/81 = 4 × 10/81 × 10 = 40/810
Add the two like fractions:
1701/810 + 40/810 = 1701 + 40/810 = 1741/810
So, 21/10 + 4/81 = 1741/810
In mixed form: 2121/810

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