Exercise with convergent and divergent lenses

[albertus50]

Homework Statement

Hello, i have gotten 3 optics exercices and i am struggling. I have looked up lessons on the internet and attempted to do the 1st exercice but i doubt i did it right. This is the statement:

Relevant Equations

A system has a convergent lens labelled L1, which has a focal length of +100mm, and a divergent lens with a focal length of -100mm. The optical centers O1and O2 of both these lenses find themselves at a distance of 90mm.

An object (A1B1), that has a height of 90mm is placed 300mms away from O1. (A1, O1 and O2 is the order of these elements on the axis).

Draw the image at a 1:3 ratio, of the A2'B2' object that is projected by this lens system.

I will insert below my attempt at resolution. I have divided every value in mm that i was given by 3 so that my final object is already the right size.
Thanks in advance for your answers!

 

[albertus50]

Oh and i forgot to add that they then ask us to calculate the distance between the A1B1 object and it's A2'B2' Image.