用竖式计算. 549+867= 356×6=验算:
计算:①3.2×1.25×0.25 ②5.8×[1÷(2.1﹣2.09)]③3150×101﹣3150 ④42÷(12+23 )⑤34×78+18×75% ⑥(78﹣516)×(59+23)
下列各题,能用简便的要用简便方法计算.①17.25+3.05+2.75+3.95 ②24×(+﹣)③×(×17﹣) ④(﹣)×(+)
①1.25×0.25×0.8×4 ②29.8﹣(9.8+2.99÷2.3)③(﹣15.3)××2.4 ④1.75×0.25+0.25×6.25⑤( +)×8+.
递等式计算.(能用简便算法的用简便方法计算)1.5×105 2.33×0.5×4 24.6+18.7+15.41.2×2.5+0.8×2.5 2.05÷0.82+33.6 9.07﹣22.78÷3.4.
3.65×4.36+6.64×3.65﹣3.65.