4 Suppose ten students in a class each flip a fair coin If a

4. Suppose ten students in a class each flip a fair coin. If a student flips heads, the student wins $25. If tails, the student wins $2. a. What is the expected value of the winnings for each individual student? (1 pt) b. What is the expected value of the total winnings of all students? (1 pt)

Solution

No of students 10

Each student outcome is independent of the other

Coin may turn Head or Tail

If head win 25, If tail win 2.

a)

Expected win = 13.5

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Total winnings would be

10 times X

Hence E(x) = 10(13.5) = 135