- CFA Exams
- CFA Level I Exam
- Topic 1. Quantitative Methods
- Learning Module 4. Probability Trees and Conditional Expectations
- Subject 1. Expected Value and Variance
CFA Practice Question
There are ten marbles in a box: one red, three yellow, and six blue. You pick one marble from the box for 75 cents. You win $5 if you pick a red marble, $1 if you pick a yellow marble, and nothing if you pick a blue marble. If you play the game once, what is your expected net gain?
B. $1.25
C. $0.05
A. $0.35
B. $1.25
C. $0.05
Correct Answer: C
Net gain: $0.8 - 0.75 = $0.05
Expected gain: 5 x (1/10) + 1 x (3/10) + 0 x (6/10) = $0.8
Net gain: $0.8 - 0.75 = $0.05
User Contributed Comments 3
User | Comment |
---|---|
wundac | much more logical with real numbers |
khalifa92 | then read the example in LOS |
thevinu | Weighted Avg - Cost |