King Fahd University of Petroleum & Minerals

King Fahd University of Petroleum & Minerals
Department of Mathematical Sciences
Stat - 211. Quiz # 4 (semester 051)
ID #:
1. If the probability of passing a college entry test is 0.85, find the probability that
among 20 candidates who are writing this test at least 2 will pass the test.
2. If on the average three cars arrive per hour at KFUPM emergency medical center.
Find the probability that there will be at most 4 car arrivals in 45 minutes.
3. The burning time of an experimental rocket is a random variable having the
normal distribution with Mean = 4.76 seconds and standard deviation = 0.04
second. What is the probability that this kind of rocket will burn any where from
4.70 to 4.82 seconds?
4. A quality control engineer inspects a random sample of 3 batteries from each lot
of 24 car batteries that is ready to be shipped. If such a lot contains 6 batteries
with slight defects. What is the probability that the inspector’s sample will contain
only one of the batteries with defects?