What value of z should we use when making a 98% confidence interval for p? 1) 2.33 2)1.75 3)It's impossible to make a 98% CI 4) 2.88
Accepted Solution
A:
Answer: Option 1) 2.33Step-by-step explanation:For the 98% confidence interval we have that the area between 0 and the z score is equal to:98% corresponds to 0.98then the area between 0 and z is half of that:a = 0.98/2 = 0.490Now you can search in a table, and you will find that the z-score for this is z = 2.326So the correct answer is 1) 2.33 where the result is rounded up.