Question

Assume that in a statistics class the probability of receiving a grade of A equals 0.30 and the probability of receiving a grade of B equals 0.30. The probability that a randomly selected student from this class will receive a grade other than an A or a B equals.
a. 0.09
b. 0.36
c. 0.40
d. 0.91

Answer 1

Answer:

c. 0.40

Step-by-step explanation:

The probability that a student has an A or B in the class can be found by simply adding up the probabilities of both. Since 0.30 + 0.30 =0.60, the probability a student has an A or B is 0.60. Now to find the probability that they don't have a A or B is represented by 1-0.60, which equals 0.40, which is our answer.

Answer 2

Answer:

c. 0.40

Step-by-step explanation:

Getting A = 0.30 chance

Getting B = 0.30 chance

Getting A and B = 0.30 + 0.30 = 0.60 chance

Getting grades other than A and B = 1 - 0.60 = 0.40 chance