Discrete Table Expected Value and Variance Help

1. After analyzing historical data, a kiosk located at Mini Park found out that the daily profit depends on the number of visitors of the day. If X is the number of visitors on a given day, the profit of the day is roughly given by:

. . . . .Profit: 5X + 0.1X²

For example, if five people visit Mini Park, then the profit will be:

. . . . .5 * 5 + 0.1 * 5² = 27.5

The probability distribution of the random variable X is given as follows:


a. What is the expected value of the daily profit?

b. What are the variance and standard deviation of the daily profit?

They want expected daily profit given the discrete table and the variance and std dev. You start with this table only and the info I gave above.

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My answers are below. Can someone double check if I have the right answers.

a. Expected Daily Profit = 60.25

b. Variance = 1956.813
Std Dev = 44.236

Thank you!

kellogs4toniee said:

1. After analyzing historical data, a kiosk located at Mini Park found out that the daily profit depends on the number of visitors of the day. If X is the number of visitors on a given day, the profit of the day is roughly given by:

. . . . .Profit: 5X + 0.1X²

For example, if five people visit Mini Park, then the profit will be:

. . . . .5 * 5 + 0.1 * 5² = 27.5

The probability distribution of the random variable X is given as follows:

X	0	5	10	20
P(X)	0.1	0.3	0.4	0.2

a. What is the expected value of the daily profit?

b. What are the variance and standard deviation of the daily profit?

---

My answers are below.

a. Expected Daily Profit = 60.25

b. Variance = 1956.813
Std Dev = 44.236

Click to expand...

Depending upon the instructor (or grader), the "exact" forms may be desired, rather than decimal approximations. But I get the same answers.