Question

Toss 3 fair coins and let x equal the number of heads observed.

a. Identify the sample points associated with this experiment and assign a value of x to each sample point
b. Calculate p(x) for each value of x
c. Construct a probability histogram for p(x)
d. What is P(x = 2 or x = 3)?

Answer 1

Well, \(X\) can be from \(0\) to \(3\).

Answer 2

There are \(2^3=8\) possible outcomes. There is \(1\) outcome for \(X=0\), \(3\) for \(X=1\), \(3\) for \(X=2\), and \(1\) for \(X=3\).

Answer 3

Hi Wio, thanks for helping. I'm not sure how to approach this problem. I understand the 2^2 = 8 part. I think we need to make a tree for this?

Answer 4

By tree, do you mean pascal's triangle?

Answer 5

Actually, do we just list it out like this?

HHH HTH HTT HHT THH TTH THT TTT

those are the sample points, correct?

Answer 6

Yeah, sure

Answer 7

Ok, so each of those are X?

Answer 8

P(1) = 3/8
p(2) = 4/8
p(3) = 1/8

am I doing this correctly?

Answer 9

No

Answer 10

you need \(p(0)\)

Answer 11

p(0) = 1/8 ?

Answer 12

yes, and your \(p(2)\) is wrong

Answer 13

p(2) = 3/8 ?

Answer 14

yes

Answer 15

thank you, i think i can solve the rest