Question

Let the random variable x represent the number of girls in a family with three children. Assume the probability of a child being a girl is 0.31. The table on the right describes the probability of having x number of girls. Determine whether the table describes a probability distribution. If it does, find the mean and standard deviation. Is it unusual for a family of three children to consist of three girls? 0 1 2 3 P(x) 0.329 0.443 0.199 0.029 Find the mean of the random variable. Select the correct choice below and, if necessary, fill in the answer box to complete your choice. O A (Round to two decimal places as needed.) O B. The table is not a probability distribution. Find the standard deviation of the random variable. Select the correct choice below and, if necessary, fill in the answer box to complete your choice. O A (Round to two decimal places as needed.) OB. The table is not a probability distribution. Is it unusual for a family with three children to have only girls ? O A. Yes, because the probability of having 3 girls is less than or equal to 0.05. O B. No, because the probability of having 3 girls is less than or equal to 0.05. O C. Yes, because the probability of having 3 girls is greater than 0.05. OD. No, because the probability of having 3 girls is greater than 0.05.

Answer 1

Page mean! 2 aplxo Đ el= - 0.443 + (2) 10.199) + (3) C 2.029) 0.443+ o.398 + 087 0.928 All - 0.93 # Ex²) zu²p(x) 0.443+ (4) 10.199) + g (0.929) =o.443 + 0.796 to.261 =1.5 6 = Elx?)-(-42 1.5 - (0.93)2 8 = o 80 P(x-3) = 0.029 co.os 6 - Ans: A. Yes, because the probability of having a gives is less than or equal to o.os.