Question

Question 7 Not yet anowered Points out of 7.00 g qestion Independent random samples from two regions in the same area gave the following chemical measurements (ppm). Assume the population distributions of the chemical are mound-shaped and symmetric two regions for these Region I: 1-12 981 726 686 496 657 627 815 504 950 605 570 520 Region 11: 2-16 1024 830 526 502 539 373 888 685 868 1093 1132 792 1081 722 1092 844 Let μ1-678 be the population mean and σ.-164 be the population standard deviation for Let μ2-812 be the population mean and σ2-239 be the population standard deviation for x2. Determine and examine the 90% confidence interval for μ 1-12. Does the interval consist of numbers that are all positive? all negative? or different signs? At the 90% level of confidence, is one region more interesting that the other from a gcochemical perspective? Select one O a. The interval contains only negative numbers. We cannot say at the required confidence level that one region is more interesting than the other. O b. The interval contains both positive and negative numbers. We can say at the required confidence level that one region is more interesting than the other. O e. The interval contains only positive numbers We cannot say at the required confidence level that one region is more intcresting than the other O d. The interval contains both positive and negative numbers. We cannot say at the required confidence level that one region is more interesting than the other O e. The interval contains only positive We can say at the required confidence level that one region is more interesting than the other. numbers

Answer 1

Solution:- option a.

Explanation :- (678-812) +/- 1.645*sqrt((164^2/12)+(239^2/16))

= (-259.4025, -8.5975)
90% Confidence interval for the Z = 1.645