probability question

It’s the rainy season again, and the city experiences frequent showers throughout the day.

The weather report says that there is a P probability of rainfalls today. Raj has to step out for a meeting at the office, and would like to know the probability that it rains during the time he is on the way.


The first line of input contains the number of test cases, T. Each of the following T lines contain two numbers, P and time. P denotes the probability that it will rain today and time is the time (in minutes), it will take for Raj to reach his office.


Output should have T lines each containing answer to corresponding test case. Please round the answer to 4 decimal places.


1<= T<= 100
0 <= P<= 0.5
10 <= time <= 720
time is a perfect divisor of 1440.

Sample Input (Plaintext Link)

0 10
.5 720

Sample Output (Plaintext Link)



This is a simple probability question. We need to find the probability that it rains during the time Raj is on the way.

So probability that it won’t rain today will be (1-p)

Probability that it won’t rain when Raj is on the way = pow((1-p), time/1440) why time/1440 because probability is given for 24 hours.

Finally, probability that it will rain sometime when Raj is on his way = 1 - pow((1-p), time/1440).

I hope this helps. :slight_smile:

why have you calculated probability of not raining first,and then calculated the required probability?
why doesnt pow(p,time/1440) give answer?

I know this is the challenge from HackerEarth. You should try to solve this problem, then only can become expert.

Can someone explain how its pow(1-p, time/1440)! I can’t get why that power. // @ashish1610