F_1 = k\frac{q_1q_2}{r^2} \\ F_1 = 9*10^9*\frac{9*10^{-8}*3*10^{-8}}{r^2} = \frac{243*10^{-7}}{r^2} \\ \\ F_2 = k\frac{ (\frac{q_1+q_2}{2})^2 }{r^2} \\ F_2 = 9*10^9*\frac{ (\frac{9*10^{-8}+3*10^{-8}}{2})^2 }{r^2} = 9*10^9*\frac{36*10^{-16}}{r^2} = \frac{324*10^{-7}}{r^2} \\ \\ \frac{F_1}{F_2} = \frac{\frac{243*10^{-7}}{r^2}}{ \frac{324*10^{-7}}{r^2} }= \frac{243}{324} =0.75Ответ: \frac{F_1}{F_2} = 0.75