Answer:
Ursula wrote 5.815 + 6.021 as
![5 (815)/(1000)+6 (21)/(1000)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/awk4f96f4sft5pwur5vrljyapi29qlnjsl.png)
Solution:
Given, Ursula wrote the sum 5.815 + 6.021 as a sum of two mixed numbers.
We have to find What sum did she write?
Decimals can be written as fractions with denominators that are powers of 10
![5.815+6.021=(5815)/(1000)+(6.021)/(1000)=(5000+815)/(1000)+(6000+21)/(1000)=5 (815)/(1000)+6 (21)/(1000)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/9los2r8pwjo6usoydujsyojl29gn0m3jdv.png)
We could simplify the fractions further more, but then the denominators would be different, so leave the fractions as they are.
Hence Ursula wrote 5.815 + 6.021 as
![5 (815)/(1000)+6 (21)/(1000)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/awk4f96f4sft5pwur5vrljyapi29qlnjsl.png)