Assignment #4Question 1. If ? represents the number of heads obtained in three tosses of a fair coin, (Create the table for both parts) (a) Find the probability distribution of ?. (b) Find...

I have attached the file with the questions I would like to be answered. I can't use excel calculations for this, it has to be written out. I've tried answering them and I've got them wrong twice. I'm not sure where I am going wrong.


Assignment #4 Question 1. If ? represents the number of heads obtained in three tosses of a fair coin, (Create the table for both parts) (a) Find the probability distribution of ?. (b) Find the expected value and the standard deviation. Question 2. A school newspaper reporter decides to randomly survey 12 students to see if they will attend Tet (Vietnamese New Year) festivities this year. Based on past years, she knows that 20% of students attend Tet festivities. We are interested in the number of students who will attend the festivities. (a) Give the distribution of ?. ?~ _____(_____,_____) (b) How many of the 12 students do we expect to attend the festivities? (c) Find the probability that at most four students will attend. (d) Find the probability that more than two students will attend. (e) Find the standard deviation. Question 3. Suppose that about 80% of graduating students attend their graduation. A group of 25 graduating students is randomly chosen. (a) Give the distribution of ?. ?~ _____(_____,_____) (b) How many are expected to attend their graduation? (c) Find the probability that 18 students attend. (d) Find the standard deviation.