Answer :
In decimal form, the answer would be 11.836. However, you need it in mixed numbers. 11 and 836/1000 or, reduced, 11 and 209/250
Answer
11 209/250
Explanation
5.815 + 6.021
First add the numbers the way they are.
5.815
+6.021
11.836
The whole number is 11.
11.836 = 11 + 0.836
0.836 = 836/1000
Dividing byy 4 we get,
0.836 = 836/1000 = 209/250
∴ 11.836 = 11 209/250