A thin convex lens of focal length 5 cm and a thin concave lens of focal length 4 cm are combined together (without any gap) and this combination has…

A thin convex lens of focal length $\displaystyle 5$ cm and a thin concave lens of focal length $\displaystyle 4$ cm are combined together (without any gap) and this combination has magnification $\displaystyle m_1$ when an object is placed $\displaystyle 10$ cm before the convex lens. Keeping the positions of convex lens and object undisturbed a gap of $\displaystyle 1$ cm is introduced between the lenses by moving the concave lens away, which lead to a change in magnification of total lens system to $\displaystyle m_2$. The value of $\displaystyle \left|\frac{m_1}{m_2}\right|$ is $\displaystyle \_\_\_\_$.