挖一个圆柱形的蓄水池,已知它的底面直径是3m,池深2.5m.在水池的底面和内壁抹上水泥,每平方米用水泥2.4kg,共需水泥多少千克?
计算下面各题,能简算的要简算. 8.5×〔(2.36+2.42)÷0.25〕 3.9÷(1.3+0.6)×6205×99 4.25×6.3+3.7×4.2525.6﹣7.49﹣2.51〔2.5﹣(6.8﹣4.9)〕×0.8.
递等式计算:(能简便计算的用简便方法计算) (1)3.6×1.25+0.32÷0.4 (2)0.45×78.2+20.8×0.45+0.45 (3)14.5+27.3+12.7+45.5 (4)(0.25+0.125)÷(0.75×0.4) (5)6500÷0.125÷0.8 (6)[(3.8﹣2.5)×0.4﹣0.1]÷0.04.
8.6×10.1 5.6×(12.5﹣8.5÷0.85) [(8.1﹣5.6)×0.9﹣1]×0.4 8.25×4.08+0.75×4.08+4.08 1.84÷[(28.02+11.98)×(62.8﹣62.3)].
脱式计算,能简算的要简算. 98.9×998.53﹣(2.25+3.53)0.725÷0.5÷0.2 0.25×7×4×0.62.7×3.6+1.4×2.780.8×101﹣80.8.
下面各题怎样算简便就怎样算. 3.28×4.6+6.72×4.60.25×1.25×0.4 9.73×2.8﹣4.73×2.8.12.5×4+3.12÷1.2 25.2﹣(7.8﹣2.6)×1.314.08÷[0.8×(7.93﹣2.43)].