For convex lens,
Focal length, f=+20 cm
Object distance, u=−40 cm
Using lens formula, we have
1f=1v−1u
120=1v−1−40
⇒1v=120−140=2−140=140
⇒v=+40 cm
Now, for convex mirror, we have
Focal length, f=R2=202=+10 cm
Object distance, u=+(40−15) cm=+25 cm
Using mirror formula, we have
1f=1v+1u
110=1v+125
⇒1v=110−125=5−250=350
⇒v=+503 cm
∴ The final image is formed at a distance of 503 cm from the convex mirror or at a distance of (503 +15)cm=953cm from the convex lens.
The final image is a virtual image.
![782895_522640_ans_7a5f7f3a1c5640ea8c853a2df4bb1a38.jpg](https://search-static.byjusweb.com/question-images/toppr_ext/questions/782895_522640_ans_7a5f7f3a1c5640ea8c853a2df4bb1a38.jpg)