Question

Find the expected value and variance of the number of heads appearing when to fair coins are tossed

Answer 1

50% of the chances are for heads

Answer 2

Answer:

1/2 or 50%.

Step-by-step explanation:

The total outcome will be A = { HH, HT, TH, TT }.

Now, according to the question we have to find the number of heads so, we take that x = number of heads.

Therefore,

The number of heads will be x = 0   1       2.

So, the probability will be p(x) = 1/4 2/4   1/4.

Hence, the value of mean =  Summation of ( pi * xi) which will be given as     (1/4 * 0) + (2/4 * 1) + (1/4 * 2)= 1

So, the value of the variance will be = summation of the [(pi * xi²)  - (pi * xi)²].

Which on solving we will get that= [(1/4 * 0) + (2/4 * 1) + (1/4 * 4)] - 1².

= 1/2 or 50%.