小明从甲地到乙地,去时每小时走5千米,回来时每小时走7千米,来回共用4小时,小明去时用了多长时间?
脱式计算,能简算的要简算.(1)(2)2.5×0.875+0.25×1.25(3)(4).
脱式计算.()×0.25 [3.6﹣(1.6+)﹣]××[﹣(﹣0.25)] (1+)×(1+)×(1+)×(1+)×(1+)
计算:①+﹣= ②3.2﹣0.85﹣1= ③3.2×﹣÷2= ④1.725×4×0.5=⑤(+)÷= ⑥1.8×0.72+1.28×1.8= ⑦2÷(﹣)= ⑧57.6÷[(1.25+25%)×0.32]=.
直接写得数.3.86+2.4= 7.6﹣0.56= 4.5×102= 3.25+2.3+1.75=361+199= 7÷0.4= 4= =2.5×32= = 0.1÷0.01= 3.47﹣(2.5+0.47)=4768÷791≈ 12÷= 1÷== 5.58÷0.78≈4.98×7.11≈ = =
用你最喜欢的方法计算.1.25×0.25×32 (0.25+)÷(﹣)×0.25+×[(8.7﹣7.5)÷0.2]×0.153.75×58.3÷58.3×6.54÷3.75÷65.456×(+﹣)