ГДЗ по математике 5 класс Мерзляк Задание 171

\[\boxed{\ \mathbf{171\ (171)}.\ Еуроки\ - \ ДЗ\ без\ мороки}\]

\[1)\ (42 + 37) + 58 =\]

\[= (42 + 58) + 37 = 100 + 37 =\]

\[= 137\]

\[2)\ 29 + (98 + 71) =\]

\[= (29 + 71) + 98 = 100 + 98 =\]

\[= 198\]

\[3)\ (215 + 818) + 785 =\]

\[= (215 + 785) + 818 =\]

\[= 1000 + 818 = 1818\]

\[4)\ 634 + (458 + 166) =\]

\[= (634 + 166) + 458 =\]

\[= 800 + 458 = 1258\]

\[5)\ 183 + 732 + 268 + 317 =\]

\[= (183 + 317) + (732 + 268) =\]

\[= 500 + 1000 = 1500\]

\[6)\ 339 + 584 + 416 + 661 =\]

\[= (339 + 661) + (584 + 416) =\]

\[= 1000 + 1000 = 2000\]

\[= 20\ 000 + 8000 = 28\ 000\]

\[= 9000 + 30\ 000 = 39\ 000\]