\[\boxed{\mathbf{243\ (243)}.\ Еуроки\ - \ ДЗ\ без\ мороки}\]
\[1)\ 374 + x;\ \ \ x = 268:\]
\[374 + 268 = 642.\]
\[2)\ 374 - x;\ \ x = 268:\]
\[374 - 268 = 106\]
\[3)\ a + b + 988;\ \ \ a = 714;\ \ b =\]
\[= 569:\]
\[714 + 569 + 988 = 2271\]
\[4)\ a - 314 + 625 - c;\ \ \ a =\]
\[= 836;\ \ b = 442:\]
\[836 - 314 + 625 - 442 = 705\]