Posted by **Student** on Sunday, August 24, 2008 at 11:00pm.

Need major help on this one. Sooo confused...

Binomial distribution to solve the problems. There is a 60 percent probability that a store will sell one of Red bags to any customer who comes into the shop and views the bags. Out of the next 7 people who come into the shop, what is the probability that 3 people will buy a bag? What is the probability that more than four people will buy the bag?

- Statistics -
**drwls**, Monday, August 25, 2008 at 11:07am
The probability of three purchases after seven customer visits is

P(3) = (0.6)^3*(0.4)^4*C(7,3)

where C(7,3) is the binomial coefficient

C(7,3) = 7!/(4!*3!) = 70

I get 0.387 for the answer.

For P(n>4), add P(5), P(6) and P(7)

For an explanation of how the probability relates to the binomial coefficient, see

http://en.wikipedia.org/wiki/Binomial_coefficient

- Statistics -
**drwls**, Monday, August 25, 2008 at 4:20pm
7!/(4!*3!) = 5*6*7/(1*2*3)= 210/6 = 35

You are right

## Answer this Question

## Related Questions

- statistics - Assume a binomial probability distribution has p = .60 and n = 200...
- Statistics - Assume it is known that the probability of birth is equal in all ...
- Binomial and Poisson distribution - A machine produces ribbon in which flaws ...
- Statistics - Assume that a procedure yields a binomial distribution with n=3 ...
- Statistics - A shoe store knows that the purchase amount by its customers is a ...
- statistics - A popular retail store knows that the purchase amounts by its ...
- Statistics - Assume that a procedure yields a binomial distribution with a trial...
- Statistics - Assume that a procedure yields a binomial distribution with a trial...
- statistics - Consider a binomial experiment with 20 trials and probability 0.45...
- STATISTICS - (a) With n=12 and p =0.4 find the binomial probability that p(9) by...