In 2016, the mean score on the AP Art History exam was 3.8, with a standard deviation of 1.2. The mean score on the AP English exam was a 2.9, with a standard deviation of 1.7. What is the combined mean and standard deviation for these exams?

A.) Mean, 0.9; standard deviation, 0.2
B.) Mean, 3.35; standard deviation, 2.9
C.) Mean, 3.35; standard deviation, 1.45
D.) Mean, 6.7; standard deviation, 2.08
E.) Mean, 6.7; standard deviation, 4.33

The mean is given by:

And the standard deviation would be:

And the distribution for X+Y would be:

And the best answer would be:

D.) Mean, 6.7; standard deviation, 2.08

Step-by-step explanation:

Let X the random variable who represent the AP Art History exam we know that the distribution for X is given by:

Let Y the random variable who represent the AP English exam we know that the distribution for X is given by:

We want to find the distribution for X+Y. Assuming independence between the two distributions we have:

The mean is given by:

And the standard deviation would be:

And the distribution for X+Y would be:

And the best answer would be:

D.) Mean, 6.7; standard deviation, 2.08

answer: a) (0,0), (1,1), (2,8), and (3,27).

step-by-step explanation:

0^3=0

1^3=1

2^3=8

3^3=27

in effect, the exponential equation for this would me y=3^x. each x-coordinate cubed is giving the y coordinate, so a is your answer : )

both equations and proportions are better.