A fair die is rolled 10 times. Find the expected value of:a) the sum of the numbers in the ten rolls;b) the number of multiples of three in the ten rolls;c) the number of different faces that appear in the ten rolls. (Hint:Use the indicator method. LetAibe the event that theith face appears at least once.)

a) 3.5

b) 3.33

c)

Step-by-step explanation:

As given,

A fair die is rolled 10 times

a)

Expected value of Sum of the number in 10 rolls =

                                                                                = 3.5

∴ we get

Expected value of Sum of the number in 10 rolls = 3.5

b)

Ley Y : number of multiples of 3

Y be Binomial

Y - B(n = 10, p = )

Now,

Expected value = E(Y) = np = 10×  = 3.33

c)

Let m = total number of faces in a die

⇒m = 6

As die is roll 10 times

⇒n = 10

Now,

Let Y = number of different faces appears

Now,

Expected value, E(Y) = m - m

                                  =

c.

step-by-step explanation:

she should of added 9^2 and 12^2. that is because it is a^2+b^2=c^2. c^2 is the hypotenuse and should always be bigger than the other two numbers. which is why she should of added 9 squared and 12 squared together instead of 15 squared.