①506﹣397 ②323﹣189 ③467+997 ④987﹣178﹣222﹣390．
能简便的用简便方法计算．30×（+） ÷[×（﹣）] 5÷+÷5÷+× ×（﹣）÷ ×﹣÷．
计算（能简算的要简算）．（15+）× ﹣× 13×+×1587× ××32 +×．
怎样简便就怎样算×72﹣×23 ×25×40×．
能简算的要简算（+）÷÷+×842000÷125÷8 ×[﹣（+）]．
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