Please explain 11313 12687 Construct a 98 confidence interv

Please explain :-

(113.13, 126.87)

Construct a 98% confidence interval estimate for the population mean given the following values: x = 120 sigma = 20 n = 50? choose one of these 4 answers (113.13, 126.87) (113.67, 126.33) (117.46, 122.54) (113.41, 126.59) Please explain :-

Solution

=120 +

113.410 <126.590

(113.41, 126.59)-----correct answer-100% sure