Answer:
![(D)E[ X ] =np.](https://tex.z-dn.net/?f=%28D%29E%5B%20X%20%5D%20%3Dnp.)
Step-by-step explanation:
Given a binomial experiment with n trials and probability of success p,
Since each term of the summation is multiplied by x, the value of the term corresponding to x = 0 will be 0. Therefore the expected value becomes:
Now,
Substituting,
Factoring out the n and one p from the above expression:
Representing k=x-1 in the above gives us:
This can then be written by the Binomial Formula as:
![E[ X ] = (np) (p +(1 - p))^{n -1 }= np.](https://tex.z-dn.net/?f=E%5B%20X%20%5D%20%3D%20%28np%29%20%28p%20%2B%281%20-%20p%29%29%5E%7Bn%20-1%20%7D%3D%20np.)
Answer:
7
Step-by-step explanation:
if the number is x then you know 2x-9=5
2x=14
x=7
so the number is 7
This problem basically already gives you X, you just have to simplify.
To complete this problem all you have to do is divide 11 by 9.6
11 / 9.6 = 1.15
So X = 1.15
In rolling one die, there are 6 possible outcomes because each die has 4 faces. The number of outcomes when rolling n dice is equal to 6^n. By this, the number of outcomes when 2 dice are rolled is 36, 216 for 3 dice, and so on.
