Решебник по математике 6 класс Перова рабочая тетрадь | Страница 9

\[\boxed{\text{24.}}\]

\[578 - 200 = 378\]

\[846 - 126 = 720\]

\[900 - 360 = 540\]

\[578 + 200 = 778\]

\[846 + 54 = 900\]

\[900 + 28 = 928\]

\[\boxed{\text{25.}}\]

\[510 + 90 = 600\]

\[510 + 140 = 650\]

\[510 + 490 = 1000\]

\[510 + 248 = 758\]

\[890 - 190 = 700\]

\[890 - 250 = 640\]

\[890 - 570 = 320\]

\[890 - 810 = 80\]

\[\boxed{\text{26.}}\]

\[800 - 267 + 400 =\]

\[= 533 + 400 = 933\]

\[446 + 385 - 407 =\]

\[= 830 - 407 = 423\]

\[392 + 485 - 262 =\]

\[= 130 + 485 = 615\]

\[317 + (800 - 642) =\]

\[= 317 + 158 = 475\]

\[704 - (238 + 337) = 129\]

\[805 - (853 - 448) =\]

\[= 805 - 405 = 400\]