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41 votes
41 votes
theme: random variables, probability distributions and expected valueJanet plays a dice game. If she rolls a 1, she wins $3 while if she rolls a 2, she wins $1. If she rolls a 3,4, or5, she loses $1 and if a 6 is rolled, she doesn't win or lose. Find the expected value of this dice game. •Round to the nearest cent. Do not round until the final calculation.

User George Robinson
by
2.8k points

1 Answer

15 votes
15 votes

Expected value = $0.17

Step-by-step explanation:

we find the probability of each numbers

Total numbers = 6

probability of 1 = 1/6

probability of 2 = 1/6

probability of 3 = 1/6

probability of 4 = 1/6

probability of 5 = 1/6

probability of 6 = 1/6

Expected value = sum of (the probabilty of each number × the amount for rolling each)

A win = positive while a loss is negative

no win or loss = 0

rolls a 1, wins $3; if she rolls a 2, she wins $1. If she rolls a 3,4, or5, she loses $1 and if a 6 is rolled, she doesn't win or lose

Expected value = (1/6 × 3) + (1/6 × 1) - (1/6 × 1) - (1/6 × 1) - (1/6 × 1) + (1/6 × 0)

= 3/6 + 1/6 - 1/6 - 1/6 -1/6 + 0 = 1/2 -2/6 = 1/2 - 1/3

Expected value = 0.5 - 0.33

Expected value = 0.17 (nearest cent)

Hence, it means Janet gained money.

User Thonnor
by
2.8k points
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