求未知数x。(1)5(x﹣3)=4.5 (2)x:3.6=:
(1)238÷238(2)
(1)×39 + ×27 (2)18.25×11 - 17÷ (1 - )
(1)64× (2) 54÷17
(1)×8(2)75×
计算:(9+7)÷(+)