The probability that a 3 year old battery works is .7 and a graphing calculator requires 4 batteries to work. Ms. Harrison find batteries that are 3 years old in the back of the closet. What is the probability that she puts them in a calculator that works?
What is .2401
100
Jeremy takes a guess on a multiple choice test in Chinese. Each question has options a, b, c, d, e, and f. What is the average number of questions he has to answer before he gets one correct?
What is 6?
100
Suppose X has a binomial distribution with n =500 and p =.3. Find the mean and standard deviation of the distribution.
What is mean = 150 and standard deviation = 10.25
200
The probability that a telemarketing employee reaches a live person is .11. Suppose they call 20 people in a night. What is the probability that they reach at least 5 people?
What is .061
200
On Jeremy's multiple choice test, what is the probability that the first time he gets one right is on the 4th question?
What is .096
200
The probability that a person who is a lady and who is at least 40 years old colors her hair is .64. Suppose you survey 1000 women. What is the probability that more than 400 do not color their hair.
What is .0041
300
nC5(p)^5(.71)^8. What is n? What is p? What is the mean of the distribution?
What is n=13, p =.29, mean =3.77
300
A basketball player has a history of making his free throws 45% of the time. What is the probability that he will make his first free throw on his 5th try in a game?
What is .041
300
In 1997 the Center for Disease Control said that 20% of teenagers carry a weapon. Suppose that 300 teenagers walked into the drivers license facility on a given day. What is the probability that more than 50 of them carried some sort of weapon?
What is .9265
400
It is estimated that 10% of drivers turn on their blinker before changing lanes. In a random sample of 4 drivers, what is the probability that at least one person uses his or her blinker when changing lanes?
What is .3439
400
A quarterback completes 47% of his passes. Construct a probability distribution table (out of n=5) for the number of passes attempted before the quarterback has a completion.
What is n=1,2,3,4,5 and p -.47, .2491, .1320, .07, .037
400
Explain why the normal approximation can be used when n = 100 and p =.9