1.仔细想.认真填。-|||-(1) dfrac (7)(5)times () =0.1times 0 -1=1.5× () ~ () /a(a>0)-|||-:-|||-(2)算式 dfrac (1)(2)div dfrac (6)(7)times dfrac (5)(3)div dfrac (2)(3)times dfrac (2)(7)=dfrac (3)(20) 中有一个运算符号写错了,把它改成正确的算式是-|||-(3)比一比,在○里填上">""<"或"="-|||-.dfrac (5)(8)div dfrac (2)(3) ○ dfrac (5)(8)-|||-dfrac (4)(5)div 3 ○ dfrac (4)(5)-|||-dfrac (9)(7)div 1 ○ dfrac (9)(7)-|||-.div dfrac (8)(9) (12-|||-dfrac (1)(4)div dfrac (4)(3) ○ dfrac (1)(4)-|||-div 1 ○a(a不等于0)-|||-我发现:两个不为0的数相除,如果除数小于1 那么商北-|||-() 被除数;如果除数大于1,那么商此 () 设除数;-|||-如果除数等于1,那么商就 () 被除数。-|||-(4)工厂里新引进了机械手臂,它拧紧1个螺丝只需 dfrac (1)(2) 秒,它1分钟可以拧紧 () 个-|||-螺丝。-|||-(5)一个三角形铁片,它的面积是 dfrac (3)(5)(m)^2 ,底是 dfrac (3)(2)m ,这条底边上的高是 () m。-|||-2.小明在写作业时,不小心将墨水洒在了本子上,导致题目有些看不清了,请你先推理出题-|||-目的算式,并在旁 边 重新计算出来。-|||-(1) dfrac (11)(12)div -|||-=times dfrac (3)(4)times 4-|||-=dfrac (11)(16)times -|||-=dfrac (11)(4)-|||-(2) .dfrac (3)(5)lt dfrac (1)(8)+dfrac (2)(5)div -|||-=dfrac (2)(5)+dfrac (2)(5)times dfrac (1)(8)-|||-=dfrac (3)(40)+-|||-=-|||-3.小小神算手。-|||-(1)直接写得数。-|||-.dfrac (9)(8)div 3=-|||-dfrac (5)(17)div dfrac (5)(34)=-|||-dfrac (1)(12)div 5=-|||-.dfrac (22)(3)div dfrac (11)(4)=-|||-https:/img.cdnjtzy.com/zyb_46948494165279d6607ee3900d03db68.jpg.8div dfrac (6)(25)=-|||-dfrac (5)(6)times dfrac (12)(5)=-|||-dfrac (9)(16)div dfrac (6)(7)=-|||-dfrac (8)(3)div dfrac (3)(8)=-|||-(2)计算,能简算的要简算。-|||-dfrac (4)(7)div dfrac (8)(3)+dfrac (3)(7)times dfrac (3)(8)-|||-(dfrac (7)(12)+dfrac (5)(18))div dfrac (35)(36)-|||-dfrac (5)(6)times dfrac (7)(13)+dfrac (6)(13)div dfrac (6)(5)+dfrac (5)(6)