Question

6. Suppose that a fair coin is tossed 2 times, and the result of each toss (H or T) is recorded.

Answer 1

Answer:

a) $S= {HH, HT, TH, TT}$

b) $P(X=0) = (2C0) (0.5)^0 (1-0.5)^{2-0}= 0.25$

$P(X=1) = (2C1) (0.5)^1 (1-0.5)^{2-1}= 0.5$

$P(X=2) = (2C2) (0.5)^2 (1-0.5)^{2-2}= 0.25$

And we have the following table:

X     |     0   |     1   |      2

P(X) |  0.25 |  0.5 |  0.25

Step-by-step explanation:

Let's define first some notation

H= represent a head for the coin tossed

T= represent tails for the coin tossed

We are going to toss a coin 2 times so then the size of the sample size is $2^2 = 4$

a. What is the sample space for this chance experiment?

The sampling space on this case is given by:

$S= {HH, HT, TH, TT}$

b. For this chance experiment, give the probability distribution for the random variable of the total number of heads observed.

The possible values for the number of heads are X=0,1,2. If we assume a fair coin then the probability of obtain heads is the same probability of obtain tails and we can find the distribution like this:

$P(X=0) = (2C0) (0.5)^0 (1-0.5)^{2-0}= 0.25$

$P(X=1) = (2C1) (0.5)^1 (1-0.5)^{2-1}= 0.5$

$P(X=2) = (2C2) (0.5)^2 (1-0.5)^{2-2}= 0.25$

And we have the following table:

X     |     0   |     1   |      2

P(X) |  0.25 |  0.5 |  0.25