Answer:
1) Each group is composed of 10 people. They either saw results or don't saw results.
saw results no results Total
A 6 4 10
B 7 3 10
C 5 5 10
D 4 6 10
Total 22 18 40
Probability of a group seeing results:
Group A: 6/10 = 0.6
Group B: 7/10 = 0.7
Group C: 5/10 = 0.5
Group D: 4/10 = 0.4
Probability of a group not seeing results:
Group A: 4/10 = 0.4
Group B: 3/10 = 0.3
Group C: 5/10 = 0.5
Group D: 6/10 = 0.6
2) Groups A and B received the Power Pill.
What is the probability that a person saw results, given they received the power pill?
(6+7)/20 = 0.65
Groups C and D received the placebo.
What is the probability that a person saw results, given they received a placebo?
(5+4)/20 = 0.45
3) What is the probability that a person received the placebo, given they did not see results?
(5+6)/18 = 0.61
What is the probability that a person received the power pill, given that they did not see results?
(3+4)/18 = 0.39
