Question

If students get their assignments done on time there is an 80% chance of earning a good grade in the class. If the assignments are finished during class or late then there is only a 30% chance of earning a good grade in the class. If the assignments are not done at all then there is only a 5% chance of earning a good grade in the class. In a certain class, 50% of the students have the assignments completed on time, 40% finish during class, and 10% do not do their assignments. If a student from this class is selected at random, what is the probability that student has a good grade?

Answer 1

Answer:

Probability that student has a good grade = 0.525

Step-by-step explanation:

Given

Chances of earning a good grade when assignments are done on time = 0.80

Chances of earning a good grade when assignments are finished during class or late = 0.30

Chances of earning a good grade when assignments are not done at all = 0.05

% of students who completed assignment on time = 0.50

% of students who completed assignment  during class = 0.40

% of students who did not completed assignment at all = 0.10

Probability that student has a good grade

= (0.80 *0.50) + (0.30*0.40) + (0.05*0.10)

= 0.525