Question

20. A researcher compared test scores between two school districts A sample in district A gave a sample mean of 72, and a sample standard deviation of 10. A sample in district B gave a sample mean of 114, and a sample standard deviation of 20. Scoring 64 in district A is comparable to what score in district B? (a) 98 (b) 92 (c) 86 (d) 80 (e) 74 21. The daily milk production of a new breed of cows has a standard deviation of 5 gallons. Researchers plan to sample 100 cows in order to estimate the mean amount. What is the probability that the sampling error will not exceed 0.6 gallon? (a) 0.0956 (b) 0.2743 (c) 0.5478 (d) 0.7699 (e) 0.8845

Answer 1

ag sal sample A mean = 72 sample A standard deviation =10 Sample B mean =114 Sample B standard deviation=20 X be the scare school A district i e, x=64 let y be the scare of school B district Standard narmal variate for x will X-X 64-72 =Z (X= sample similary far y mean of x & paint estimate Z = Y- 114 20 mean ) we get af papulation equating equation equation or Y-114 64-72 = y=98 scare in district B=98