We know that 25 of the class got an A on the last exam, and 30 ...

[dbose]

We know that 25 of the class got an A on the last exam, and 30 got a B. What percent got either an A or a B?
 
  a. 25 30 = 7.5
  b. 25 + 30  = 55
  c. 45
  d. We cannot tell from the information that is presented.

Question 2

We care a great deal about areas under the normal distribution because
 
  a. they translate directly to expected proportions.
  b. they are additive.
  c. they allow us to calculate probabilities of categories of outcomes.
  d. all of the above

[JaynaD87]

Answer to Question 1

B

Answer to Question 2

D