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:
15.6 ft
Step-by-step explanation:
Since the sails are similar then the ratios of corresponding sides are equal.
Comparing the shortest sides, that is
10 : 6 = 5 : 3
let the longest side be x, then using proportion
=
( cross- multiply )
5x = 78 ( divide both sides by 5 )
x = 15.6
The longest side is 15.6 ft
Answer:
5500 pounds
Step-by-step explanation:
if you mean 2¾
in 2 tons there's 4000 pounds
in ¾ of a ton there is 1500 pounds
4000 + 1500 = 5500 pounds