Question

please lease solve all questions.

2. Consider the following two variables X and Y: 4 a. (2 pts) Find the mean of X, and mean of Y b. (2 pts) Find the standard deviation of X, and standard deviation of Y C. (3 pts) Find the covariance between X and Y d. (2 pts) Find correlation coefficient between X and Y and comment on your answer. 3. The following table shows a random sample of 100 hikers and the areas of hiking preferred. Total The Coastline 18 16 34 Near lakes On Mountain peaks Female Male Total 45 25 14 25 100 a. (2 pts) What is the probability that a randomly selected person is male? Activate Wind Go to Settings to a b. (2 pts) What is the probability that a random person is female and preferred hiking on the coastline? C. (3 pts) What is the probability that a random person is female or prefers hiking on mountain peaks? d. (3 pts) What is the probability that a random person is male given that s/he prefers hiking near lakes? 11. The heights of teenagers are normally distributed with mean 170 cm and standard deviation 7.5 cm. a. (5 pts) What is the probability that the height of a random teenager is more than 173 cm? b. A random sample of 9 men is selected. i. (2 pts) What is the standard error for the sample mean? ii. (5 pts) What is the probability that the sample mean height is between 167.5 and 172.5 cm?

Answer 1

Mean of x: Elx) 드나 1+1+4 3 LE mean of X-2- mean of Y 3 15 3 Le meano b) Standard deviation of x Je haue, 2. x) 3 2019/4/14 01:05 3

Det Date: standard deriation of Y Var (y) 8.6667 二 S. D (X)141 olloiance between x tY 3 3 6-l O 2019/4/14 01:05

Comelation b co efficient betweenxe V(x) C011 (x,y) x famment os 1elated t 1112 X 2.939 0.3607 (011 (x,y)--0.9607 is This implies xy ae ea as follbws poson is female san is male ci prefetted hiking diea is coastline Hiking aiea is Nea lakes aea is an mountain peaks that randomly selected person is P18) = h(8) -mo of total male (s)hd. of total person iom giun table lo o p(B) 0, 55 2019/4/14 01:06

Date: dy that tandom persan is female t pefened the aastline л с) c)ニ 惚no, of female with hiking area coastline Total no of peson loo tha hiking on mountain peaks dt andom person is fomale or profers 4y5 2. loo that Yandom person is male qiven that near lakes te che he pefers hiki P (enD) P CD) 25/10o 41/i00 2 5 2019/4/14 01:06 P (BID)0.6097

etx Height of teena qers Pinbabil lity that height of Tondom teen aaeY is moie than 13 m is 1 7.5 드 PLZ > 8.4 > 34458 foom stati -'' | p | χ > ) 731 0-34 458 6)I andon-Sample-n tandord eroi ot Sample meant

We know if xu NLL)then Date: Sample mean, X , dIn) standand e11o1 of sample mectn is 1- 5 S,F(X) 2-5 ニ that sample mean height is betueen 167-5< X < 172:51-1 111.5 172.5 on: Le 2 2.5 1-(2 χ 0-1 5866) ニ PD67-5ーく1725]ー0.68268