Answer:
The answer is -8
Step-by-step explanation:
First, add 8 to both sides to separate the 3r from the rest of the terms. Now you have 3r = -24. Divide both sides by 3, and now you have r = -8
Answer:
40 questions
Step-by-step explanation:
This is simple
Divide 34 by .85 (Which is 85% in a decimal)
There were 40 questions
Answer:
Step-by-step explanation:
The main idea is that I would like to pay less than what I'm expecting to win, so in that way, I get a profit out of playing this game. Let X be the number of tosses until I get a Heads. By definition, this is a geometric random variable with parameter p = 1/2.
Let Y the amount I received for playing. So, we want to calculate the expected value of Y.
We can calculate it as follows
![E[Y] = 2 P(X=1)+ 4 P(X=2)+ 8 P(X =3) + \dots = \sum_{n=1}^infty 2^n P(X=n)](https://tex.z-dn.net/?f=E%5BY%5D%20%3D%202%20P%28X%3D1%29%2B%204%20P%28X%3D2%29%2B%208%20P%28X%20%3D3%29%20%20%2B%20%5Cdots%20%20%3D%20%5Csum_%7Bn%3D1%7D%5Einfty%202%5En%20P%28X%3Dn%29)
Since X is a geometric random variable, we have that 
Then,
So, we expect to have an infinite amount. Given this, we can pay as much as we want to play the game.
Answer:
-5a(2a^3+a-1)
Step-by-step explanation:
I factored -5a out of 5a -5a^2-10a^4
hope this helped you