The electric lines of force are entering charge q1​ ; so, it is negative. On the other hand, the lines of force are originating from charge q2​ ; so, it is positive. If the lines are drawn in proportion to the charges, then q2​q1​​=186​ ⇒q2​q1​​=31​ 6 lines are entering q1​ and 18 are coming out of q2​ .