\[\boxed{\text{288\ (288).\ }\text{Еуроки\ -\ ДЗ\ без\ мороки}}\]
Пояснение.
Решение.
\[a = 1,0539\ldots;\ \ \ b = 2,0610\ldots\]
\[\textbf{а)}\ a = 1,0539\ldots \approx 1,1\]
\[b = 2,0610\ldots \approx 2,1\ \ \]
\[a + b = 1,1 + 2,1 = 3,2.\]
\[\textbf{б)}\ a = 1,0539\ldots \approx 1,05\]
\[b = 2,0610\ldots \approx 2,06\]
\[a + b = 1,05 + 2,06 = 3,11.\ \]
\[\textbf{в)}\ a = 1,0539\ldots \approx 1,054\]
\[b = 2,0610\ldots \approx 2,061\]
\[a + b = 1,054 + 2,061 = 3,115.\text{\ \ }\]