Water Trace metals found in wells affect the taste of drinking water, and high

Chapter 8, Problem 72

(choose chapter or problem)

Get Unlimited Answers
QUESTION:

Water Trace metals found in wells affect the taste of drinking water, and high concentrations can pose a health risk. Researchers measured the concentration of zinc (in milligrams/liter) near the top and the bottom of 10 randomly selected wells in a large region. The data are provided in the table below.30 (a) Construct and interpret a 95% confidence interval for the mean difference m in the zinc concentrations from these two locations in the wells. (b) Does your interval in part (a) give convincing evidence of a difference in zinc concentrations at the top and bottom of wells in the region? Justify your answer. Well: 1 2 3 4 5 6 7 8 9 10 Bottom: 0.430 0.266 0.567 0.531 0.707 0.716 0.651 0.589 0.469 0.723 Top: 0.415 0.238 0.390 0.410 0.605 0.609 0.632 0.523 0.411 0.612 Difference: 0.015 0.028 0.177 0.121 0.102 0.107 0.019 0.066 0.058 0.111

Questions & Answers

QUESTION:

Water Trace metals found in wells affect the taste of drinking water, and high concentrations can pose a health risk. Researchers measured the concentration of zinc (in milligrams/liter) near the top and the bottom of 10 randomly selected wells in a large region. The data are provided in the table below.30 (a) Construct and interpret a 95% confidence interval for the mean difference m in the zinc concentrations from these two locations in the wells. (b) Does your interval in part (a) give convincing evidence of a difference in zinc concentrations at the top and bottom of wells in the region? Justify your answer. Well: 1 2 3 4 5 6 7 8 9 10 Bottom: 0.430 0.266 0.567 0.531 0.707 0.716 0.651 0.589 0.469 0.723 Top: 0.415 0.238 0.390 0.410 0.605 0.609 0.632 0.523 0.411 0.612 Difference: 0.015 0.028 0.177 0.121 0.102 0.107 0.019 0.066 0.058 0.111

ANSWER:

Step 1 of 8

(a)

Determine the difference between bottom and top of each pair of data.

Sample1

Sample 2

Difference D

0.43

0.415

0.015

0.266

0.238

0.028

0.567

0.39

0.177

0.531

0.41

0.121

0.707

0.605

0.102

0.716

0.609

0.107

0.651

0.632

0.019

0.589

0.523

0.066

0.723

0.612

0.111

mean

0.0804

sd

0.0523

Add to cart


Study Tools You Might Need

Not The Solution You Need? Search for Your Answer Here:

×

Login

Login or Sign up for access to all of our study tools and educational content!

Forgot password?
Register Now

×

Register

Sign up for access to all content on our site!

Or login if you already have an account

×

Reset password

If you have an active account we’ll send you an e-mail for password recovery

Or login if you have your password back