2. As concrete cures it gains strength. The following data represents the 7 day and 28 day strength (in pounds per square inch) of a certain type of concrete. 7 Day Strength, x 28 Day Strength, y 2300 4070 3390 5220 2430 4640 2890 4620 3330 4850 2480 4120 3380 5020 2660 4890 2620 4190 3340 4630 a) Calculate r b) Calculate the least regression line c) Test whether there is a linear relationship between 7-day strength and 28-day strength. Let a=0.05

2. As concrete cures it gains strength. The following data represents the 7 day and 28 day strength (in pounds per square inch) of a certain type of concrete. 7 Day Strength, x 28 Day Strength, y 2300 4070 3390 5220 2430 4640 2890 4620 3330 4850 2480 4120 3380 5020 2660 4890 2620 4190 3340 4630 a) Calculate r b) Calculate the least regression line c) Test whether there is a linear relationship between 7-day strength and 28-day strength. Let a=0.05

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

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