Question

Small Mean Problem. Grandfather clocks have a particular market in auctions.   You are given a random sample of 20 purchases of grandfather clocks at auctions in Pennsylvania. The sample statistics are:

• Mean = $1,343.04
• Std Dev = $414.04
• C.V. = 30.83
• N = 20

You are asked to create a 90% Confidence Interval around the price for this sample.  

The t-value you would use is? I just want the answer. Use 3 decimal places for your answer and use the proper rules of rounding.

Answer 1

Given that, sample size (N) = 20

Degrees of freedom = N - 1 = 20 - 1 = 19

confidence level = 0.90

=> significance level = 1 - 0.90 = 0.10

Using t-critical value at significance level of 0.10 with 19 degrees of freedom is, tcrit = ± 1.729

=> t-critical value = 1.729