\[\boxed{\mathbf{196.}}\]
\[1)\ 430 + 20 = 450\]
\[430 - 20 = 430\]
\[При\ вычитании\ десятки\ \]
\[вычитают\ из\ десятков.\]
\[2)\ 340 + 20 = 360\]
\[340 - 20 = 320\]
\[560 + 30 = 590\]
\[560 - 30 = 530\]
\[750 + 40 = 790\]
\[750 - 40 = 710\]