Collecting Dataand Expected Value

When collecting data, there are several methods:

Experimental Study: The researcher takes actions to get results

Observational Study: The researcher does not take actions, but simply watches to see results.

Simulation: A task in which the real circumstances are simulated, either in fact, or by means of a set of mathematical formulae each.

Survey: The researcher gives surveys to collect data.

The number of people who wash their hands in the restroom

If a new medicine is ready to be approved by the FFA.

Can you grow flowers in outer space?

How many times per week a person eats chicken.

What type of data collection would you use to find:

(see worksheet)

To know the average age of your class

To know that average age of the united states

To know how many people watched Big Bang Theory last night.

What type of survey would you use for.

Expected value is a measurement of the center of a probability distribution. The formula is derived from that of the mean. Over the long run of several repetitions of the same probability experiment, if we averaged out all of our values of the random variable we would obtain the expected value

E(X) = x1p1 + x2p2 + x3p3 + . . . + xnpn

example: If I rolled a dice 100 times, what would the expect value be?

If you flip a coin 3 times, what is the expected value for the number of heads?

A game consists of rolling a colored die with three green sides, two red sides, and one blue side. A roll of a red loses. A roll of blue pays $6.00. A roll of green pays $2.00. What is a "fair" price to pay to play? (What is the expected value of one play?)

A department store wants to sell eight purses that cost the store $40 each and 32 purses that cost the store $10 each. If all purses are wrapped in forty identical boxes and if each customer picks a box randomly, find

(a) each customer's expected value if a customer pays $15 for a box.

(b)the department store's total expected profit (or loss) during this sale. 

Assume that the odds against a certain horse winning a race are 5 to 2. If a better wins $14 when the horse wins, how much should the person bet to make the game "fair"?