\[\boxed{\mathbf{262}\mathbf{\ (231)}.\ Еуроки\ - \ ДЗ\ без\ мороки}\]
\[1)\ (176 + 343) - 243 =\]
\[= 176 + (343 - 243) =\]
\[= 176 + 100 = 276\]
\[2)\ (684 + 915) - 484 =\]
\[= 684 - 484 + 915 =\]
\[= 200 + 915 = 1115\]
\[3)\ 1287 - (487 + 164) =\]
\[= 1287 - 487 - 164 =\]
\[= 800 - 164 = 636\]
\[4)\ 971 - (235 + 371) =\]
\[= 971 - 371 - 235 =\]
\[= 600 - 235 = 365\]