Answer:
30
Step-by-step explanation:
7! = 7*6*5*4*3*2*1 = 5040
None of the above
Answer:
66.76% probability that the levee will NEVER fail in the next 20 years.
Step-by-step explanation:
For each year, there are only two possible outcomes. Either a levee fails during the year, or no levees fail. In each year, the probabilities of levees failing are independent from each other. So we use the binomial probability distribution to solve this problem.
Binomial probability distribution
The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.

In which
is the number of different combinations of x objects from a set of n elements, given by the following formula.

And p is the probability of X happening.
In this problem we have that:
A levee was designed to protect against floods with an annual exceedance probability of 0.02. This means that 
What is the risk that the levee will NEVER fail in the next 20 years?
This is
when
. So


66.76% probability that the levee will NEVER fail in the next 20 years.
63 due to .25 being 1/4 so 15 times four is 60 and 75 divided by 25 is 3
Answer:
About 67%
Step-by-step explanation:
This is a conditional relative frequency. There are 36 students who are aged 14-17 and 24 of them skip breakfast. Therefore, the answer is 24/36 = 2/3 ≈ 67% (ans)