Answer:
1) 
2) 49.225
3) 
Step-by-step explanation:
1) To find the expected value of the dice we can use the following equation:

So in our problem the values x will be: 1/1, 1/2, 1/3, 1/4, 1/5 and 1/6 and the probavility for all values is 1/6 so the expected values will be:

2) To find the variance of the expected values we can use the equation:

So for our problem will be:



3) To find the expected value of the dice we can use the following equation:

So in our problem the values x will be: 1, 2, 3, 4, 5 and 6 and the probavility for all values is 1/6 so the expected values will be:

I think the volume of the sphere is 4 centimeters.
T= trumpets
S= saxophones
T= s-10
S= 3t
Solve for t first in first equation by substituting the second equation into the first equation like this .
T=3t-10
T-3t=10
-2t=10
T=10/-2
T=5
Now substitute your t answer to second equation to find s .
S=3(5)
S=15
So you have 5 trumpets and 15 saxophones .
I hope this helps
Answer:
C
Step-by-step explanation: