Question
number 12
3 bag's Of COURies (a) Give the sample space of X. (b) Decide the probability distribution (and its parameter/s) of the random variable X 12. Penny thinks that the amount of tip she gets per day is about $20, on average, but since there are some days when she gets no tip at all she claims the variance to be $20 as well. Assuming that the amount of tip is a positive integer and that Penny's assumptions are valid, find the chances that Penny gets exactly $2 as her daily tip. 13. Find E (X3) if X has continuous uniform distribution over (0,5). 14. A continuous random variable Y has a uniform distribution over (-1,4). Find the probability that Y is exceeds 3.1. 2
Explanation / Answer
mean = 20
std. dev. = 20
The required probability can be determined using the excel formula
=NORM.DIST(2,20,SQRT(20),FALSE)
= 0.0000271
Here the assumption made is of normal distribution and cetral limit theorem is applied.