math statistics
posted by Sherri .
If the probability of a swan drowning is 0.23, find the probability of exactly 4 out of the 7 swans drowning.
I think that the answer is:
(0.23)(0.23)(.00003404)= .000001801
is the right?
*round your answer to 3 significant digits*

p of drowning = .23
1p = prob of not drowning = .77
In general the probability of k hits in n trials is
C(n,k) p^k (1p)^(nk)
(binomial random variable )
so here we want
C(7,4)* .23^4 * .77^3
C(7,4) from Pascal's triangle of combination formula = 35
so
35 * .23^4 * .77^3 = .0447 
thank you so much!!!

If the probability of a lame leaping lord is 0.24
Respond to this Question
Similar Questions

AP Statistics
if the probability of a swan drowning is .27, find the probability of exactly 4 out of the 7 swans drowning. 
statistics
Consider a binomial experiment with 20 trials and probability 0.45 on a single trial. Use the normal distribution to find the probability of exactly 10 successes. Round your answer to the thousandths place. 
statistics
Consider a binomial experiment with 20 trials and probability 0.45 on a single trial. Use the binomial distribution to find the probability of exactly 10 successes. Round your answer to the thousandths place 
statistics
Consider a binomial experiment with 20 trials and probability 0.45 on a single trial. Use the normal distribution to find the probability of exactly 10 successes. Round your answer to the thousandths place. 
Math/Prob
Claire takes a fivequestion truefalse test. She hasn't studied, so she guesses at random. With her ESP she figures she has a 60% probability of getting any one answer wrong. A. What is the probability of getting an answer wrong? 
Statistics
A total of 16 mice are sent down a maze, one by one. From previous experience, it is believed that the probability a mouse turns right is .38 a) What is the probability that exactly 8 of these 16 mice turn right? 
Math:Probability
The probability of having homework over the weekend in math is 0.9,history is 0.6, and Spanish is 0.75. 1. What is the probability of having exactly one class that gives homework? 
stats
On the seventh day of Statistics, my teacher gave to me  seven swans aswimming. But can they swim faster than American Olympic gold medallist Michael Phelps? 
English
Read the following line from "Not Waving but Drowning." "Poor chap, he always loved larking And now he's dead" a. detached b. pleased c. objective d. critical NOT WAVING BUT DROWNING Stevie Smith Nobody heard him, the dead man, But … 
Statistics
Consider the probability that fewer than 17 out of 145 people will get the flu this winter. Assume the probability that a given person will get he flu this winter is 11%. Approximate the probability using the normal distribution. Round …