下面的横线上可以填哪些数字?(用“四舍五入”法)(1)7 ×39≈2800 (2)3 ×51≈2000.
计算,能简算的要简算 45×0.25+×17+25%×38 6.62×45+3.38÷ [1.18﹣1.18×(1﹣1.7)]÷(16﹣5)[10﹣(4+1×2)]÷2.
160÷1﹣0.75×60246×25×98+12×+117×+35×.
脱式计算,能简算的要简算. (1)(+)÷﹣ (2)10.6﹣(6.6+÷12.5%) (3)(+)÷+ (4)×+×.
计算: 8.06﹣2.73﹣5.271.25++0.75+÷+×X﹣0.75X=0.375.
用简便方法计算: 1.29+3.7+0.71+6.3528×78+472×7846.5×99+46.5 125×89×812.37﹣5.32﹣4.68 12.5×(0.8+8)