# Question: One of the saddest world statistics is the HIV AIDS rate

One of the saddest world statistics is the HIV/AIDS rate in African countries. For example, the HIV/AIDS rate in Sierra Leone among people aged 15 to 45 is reported to be 7%. If doctors were to randomly screen 250 residents of Sierra Leone in this age group, what is the

a. expected number of people in the group who have HIV/AIDS? Explain the meaning of this

expected value.

b. variance of the random variable “number of people in the group who have HIV/AIDS”?

c. standard deviation of the random variable “number of people in the group who have HIV/AIDS”?

a. expected number of people in the group who have HIV/AIDS? Explain the meaning of this

expected value.

b. variance of the random variable “number of people in the group who have HIV/AIDS”?

c. standard deviation of the random variable “number of people in the group who have HIV/AIDS”?

**View Solution:**## Answer to relevant Questions

In Exercise 17, it was reported that about 1% of all airline flights scheduled to depart from US airports are canceled. You select 100 flights at random. Assuming all the binomial conditions are met, compute the In Exercise ...Use the binomial table to find the following probabilities: a. P ( x = 1), where n = 9, p = .2 b. P (x = 4), where n = 20, p = .35 c. P (3 < x < 5), where n = 15, p = .5 d. P(x > 2), where n = 10, p = .4 According to the Mortgage Bankers Association, 10% of all home mortgage loans in California were in foreclosure in the fourth quarter of 2011. Assuming this rate holds, if you randomly pick 30 California home mortgage loans, ...Use the Poisson probability function to determine the following probabilities: a. For λ = 2, P(x = 5) b. For λ = 6, P(x = 2) c. For λ = 3.5, P(x = 0) d. For λ = 2, P(2 < x < 4) DuPont produces Kevlar, a high strength (five times stronger than steel) lightweight fiber. Kirby Outfitters uses the fiber in some of its products and occasionally inspectors find a small flaw in the strands of fiber ...Post your question