Answer:
I think it would be C
Step-by-step explanation:
Answer:
Mean = 1.42
Variance = 0.58
Step-by-step explanation:
Given: X denote the number of luxury cars sold in a given day, and Y denote the number of extended warranties sold.
Also, joint probability function of X and Y are given.
To find:
mean and variance of X
Solution:
From the given joint probability function of X and Y,

Mean of X:

Variance of X:

![var(X)=E\left [ X^2 \right ]-\left ( E\left [ X \right ] \right )^2\\=\frac{31}{12}-\left ( \frac{17}{12} \right )^2\\=\frac{31}{12}-\frac{289}{144}\\=\frac{372-289}{144}\\=\frac{83}{144}\\=0.58](https://tex.z-dn.net/?f=var%28X%29%3DE%5Cleft%20%5B%20X%5E2%20%5Cright%20%5D-%5Cleft%20%28%20E%5Cleft%20%5B%20X%20%5Cright%20%5D%20%5Cright%20%29%5E2%5C%5C%3D%5Cfrac%7B31%7D%7B12%7D-%5Cleft%20%28%20%5Cfrac%7B17%7D%7B12%7D%20%5Cright%20%29%5E2%5C%5C%3D%5Cfrac%7B31%7D%7B12%7D-%5Cfrac%7B289%7D%7B144%7D%5C%5C%3D%5Cfrac%7B372-289%7D%7B144%7D%5C%5C%3D%5Cfrac%7B83%7D%7B144%7D%5C%5C%3D0.58)
Answer:
c) at most 11.1%
Step-by-step explanation:
We have the data that is 97 ± 12, with 97 being the mean and 12 the standard deviation.
Now, the percentage of people who reached them for less than 73 dollars, if it were a normal distribution:
z = (73 - 97) / 12 = - 2
so it would be, a probability of 0.0228 or 0.228%.
But we don't know what distribution it has, but we can get an idea.
A and D discarded, as they are very high values, and 73 is well below the average.
B) is still a very high value.
Therefore the answer is C, at most 11.1%
Pythagorean theorem.
a^2+b^2=c^2
This means that the square of the length of the 2 legs of a right triangle added together = the square of the length of the hypotenuses or diagonal.
If you know 2 of the values in the 3 variables a,b,c what would you do to find the missing variable value?
I will not write the exact answers to this problem. I think you can figure how to write it out yourselves.