Question

The random variable X is the number of tails obtained after tossing 4 coins. A) List the all possible outcomes. How many possible outcomes? ARe they equally likely outcomes? B) Using a table, display the probability distribution of the number of tails. C) Calculate the probability of one tail or two tails. D) Calculate the probability of at least of one tail.

Answer 1

(a) The possible outcomes are 2^4 = 16.

All the outcomes are equally likely.

The sample size is:

{TTTT, TTTH, TTHT, THTT, HTTT, TTHH, THTH, HTHT, HHTT, THHT, HTTH, THHH, HTHH, HHTH, HHHT, HHHH}

(b) The probability distribution of the number of tails is:

Number of tails	Probability
0	0.0625
1	0.25
2	0.375
3	0.25
4	0.0625
Sum	1

(c) The probability is = 0.25 + 0.375 = 0.625

(d) The probability is = 1 - 0.0625 = 0.9375

Please give me a thumbs-up if this helps you out. Thank you!