Ответ:
\[\frac1{2020}+\frac1{2022}=\frac{2022+2020}{2020\cdot2022}=\frac{4042}{2020\cdot2022}.\]
Так как \(20.21=\frac{2021}{100}\), получаем:
\[\frac{20.21}{\frac1{2020}+\frac1{2022}}=\frac{2021}{100}\cdot\frac{2020\cdot2022}{4042}=\frac{2021}{100}\cdot\frac{2020\cdot2022}{2\cdot2021}=\frac{2020\cdot2022}{200}=20422.\]
Ответ: 20422.
