Challenge III Abandaned Due to Rain

So Sorry ! Challenge III(Maths) has been abandoned due to very heavy rainfall and snowfall. Actually my brain has been washed off and I have forgot "how to do that question.." :( .
The notebook in which I had solved it, is missing.,,, So Challenge III has been called off (most probably postponed). If you get the answer do send it to arpit.nofear@gmail.com.
Till that time, new Challenge (IV) has been published. This challenge is to test your IQ level. Two questions are there for you to answer.. So start Thinking!