As part of our exercise for IBPS PO 90 day course the 1st lesson on simplification is attached here with ..Also given below is an exercises on Simplification which will help you in revising the material properly. The lectures start with basics and gradually goes into the problem solving mode with tricks to solve fast, thrown in between. Afer you complete the lecture, you will definitely be able to solve questions within the stipulated time, which I believe should not be more than 3-4 mins for a 5 question set.
The questions in the exercise have not been given answer keys deliberately for you to practice and come up with answers and engage in discussions.
Please see the exercise HERE
Enjoy Part 1 and part 2 of the lecture below
Verifying, please be patient.