Suppose we have a bag with 10 slips of paper in it. Eight slips have a 3 on them and the other two have a 9 on them. What is the expected value of the number shown when we draw a single slip of paper?

I know this was already similarly answered, however, I do not know the formula for this.

Thank you

Guest Jul 30, 2021

#1**0 **

Take each value times it's probability and sum them

3 * 1/10 + 3 * 1/10 ......+ 9* 1/10 + 9 * 1/10 =

7 * 3 * 1/10 + 2 * 9 * 1/10

21/10 + 18/10

= 3.9 ( in this case it is just the average of all of the slips)

Guest Jul 30, 2021

#3**0 **

It IS wrong....and if you read through the solution YOU should have seen why...there is EIGHT 3's, not seven.....kinda proves you are just looking for answers and not understanding/learning...don't be that guy/girl....

Take each value times it's probability and sum them

3 * 1/10 + 3 * 1/10 ......+ 9* 1/10 + 9 * 1/10 =

8 * 3 * 1/10 + 2 * 9 * 1/10

24/10 + 18/10

= 4.2 ( in this case it is just the average of all of the slips)

ElectricPavlov
Jul 30, 2021