One out of every 5000 individuals in a population carries a certain defective gene. A random sample of 1000 individuals is studied.

a. What is the probability that exactly one of the sample individuals carries the gene?
b. What is the probability that none of the sample individuals carries the gene?
c. What is the probability that more than two of the sample individuals carry the gene?
d. What is the mean of the number of sample individuals that carry the gene?
e. What is the standard deviation of the number of sample individuals that carry the gene?


Let X be the number of individuals in the sample that carry the gene. Then X is the number of successes in n= 1000 Bernoulli trials, each of which has success probability p = 0.0002. The mean of X is np= (1000)(0.0002) = 0.2. Since n is large and p is small, X ~ Poisson(0.2) to a very close approximation.



Trades & Technology

You might also like to view...

Limit switches are momentary contact (spring returned), but not maintained contacts.

Answer the following statement true (T) or false (F)

Trades & Technology

Which of the following valves would not be a good choice for isolation service?

A) Globe valve. B) Wafer valve. C) Gate valve. D) Ball valve.

Trades & Technology

What is a geothermal gradient?

What will be an ideal response?

Trades & Technology

One complete set of plans _____

a. is made for all contractors to share b. is kept in the field office for reference c. must be on site at all times d. must be given to the building inspector

Trades & Technology