Answer:
16
Step-by-step explanation:
To find the radius find the distance between (4,0) and (4,8). The radius is 8. Then multiply by 2 to find out the diameter.
Answer:
5/23
Step-by-step explanation:
23 play a sport and 5 play both an instrument and a sport so 5 out of 23 play an instrument given that they play a sport
Height would be 21 inches, depth would be 5.
Answer:
The mathematical expectation of a student who purchases 10 tickets is -$39.65.
Step-by-step explanation:
A student that purchases 10 tickets out of 2900 has a probability of winning the cruise that can be calculated as:

Each ticket cost $5, so he has spent $50 for the 10 tickets.
Then, the expected value of this operation is equal to the expected value of the earnings (probability of winning the prize multiplied by the value of the prize), minus the costs:

The mathematical expectation of a student who purchases 10 tickets is -$39.65.