Answer:
a) 0.1108
(b) 0.0173
Step-by-step explanation:
We are given that 20% of all stock investors are retired people. A random sample of 25 stock investors is taken.
Firstly, the binomial probability is given by;
where, n = number of trails(samples) taken = 25
r = number of successes
p = probability of success and success in our question is % of
retired people i.e. 20%.
Let X = Number of people retired
(a) Probability that exactly seven are retired people = P(X = 7)
P(X = 7) =
= = 0.1108
(b) Probability that 10 or more are retired people = P(X >= 10)
P(X >= 10) = 1 - P(X <= 9)
Now, using binomial probability table, we find that P(X <= 9) is 0.98266 at n = 25, p = 0.2 and x= 9
So, P(X >= 10) = 1 - 0.98266 = 0.0173.
Here is the website for the answer... I hope this helps...
P.S. I think that if you click on the link, it won't work. So, just copy and paste...
Here, let the age of student be x and teacher be 4x after 28 years, the teacher is double the age of student. So the age of teacher will be 4x+28 and student will be 2(x+28)
So,
4x+28=2(x+28)
4x+28=2x+56
4x-2x=56-28
2x=28
x=14
Therefore the age of the teacher in present will be
=4x+28
=4*14+28
=84
And age of student will be:
=x+28
=14+28
=42
Hope this helps
Answer:
:)
Step-by-step explanation:
I think the answer is 300 or over 300. Maybe even 750, I'm not really sure
19 chairs.
650-176 is 474 and 474 divided by 25 is 18.96 so round up and 19 or 18 per row