Question

In a bag, there are two $20 bills, one $10 bill, four $5 bills, and three $1 bills. If Frank picks one bill from the bag, the expected value of the bill he chooses is $:

a. 7.20
b. 8.40
c. 6.60
d. 5.80

Answer 1

The expected value of selecting one bill from the bag is $7.30, which is calculated by multiplying the value of each bill by its probability of being chosen and summing these figures. However, this value doesn't match the provided options, suggesting a possible typo.

Step-by-step explanation:

The student is asking how to calculate the expected value of randomly selecting a bill from a bag with various denominations. To determine this, we need to multiply the value of each bill by the probability of selecting that bill and then sum these products. Here's the calculation:

• There are 2 x $20 bills, so (2/10) x $20 = $4.00
• There is 1 x $10 bill, so (1/10) x $10 = $1.00
• There are 4 x $5 bills, so (4/10) x $5 = $2.00
• There are 3 x $1 bills, so (3/10) x $1 = $0.30

Now add up these amounts: $4.00 + $1.00 + $2.00 + $0.30 = $7.30.

The correct answer isn't listed among the choices, but based on the calculations, the expected value per draw is $7.30. The closest answer to this expected value is option b. $7.20, which may suggest a typo in the question or answer choices.