用合理的方法计算:(1)435+7512+25;(2)81117-3815-2715;(3)9512-(8512-7619);(4)11917-81225+51225;(5)5212×23+5114×45+5016×67;(6)(2512+358+456)÷(2112+318+416).-数学
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=34+1+40+1+42+1,
=(34+40+42)+(1+1+1),
=116+3,
=119;
(6)(2
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=(2
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=[(2+3+4)+(
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