Question

(c) Seorang ahli ekonomi berminat untuk mengkaji pendapatan pengguna di sesuatu rantau tertentu. Sisihan piawai populasi adalah $1,000. Berapakah saiz sampel perlu digunakan oleh ahli ekonomi untuk selang keyakinan 95% jika perbezaan antara had keyakinan atas dan had keyakinan bawah tidak boleh melebihi $100? An economist is interested in studying the income of consumers in a particular region. The population standard deviation is known to be $1,000. What sample size would the economist need to use for a 95% confidence interval if the difference between upper confidence limit and lower confidence limit should not be more than $100? (2%2 markah/marks)

Answer 1

we kwow the formula Margin f eror = Hhe the population standand deviaton is $10ro 6= 1000 [2 value corrupun ding to 95% Confilen ce intuval is 1.96] 2= 1196 Now Man qin g evor=$100 tnce lo0= li96 1o00 1960 l00 Vn = 19.6 => n= 384.46 и Sam ple size f 384 would the economis f Hunce, for a 950% Confiden ce in tuval if need to use the dibbuence bet ween uppu confidence linei't andd lown Contidence limi't should $ 100 . not be more thom CS Scanned with CamScanner