Question

As concrete​ cures, it gains strength. The following data represent the​ 7-day and​ 28-day strength in pounds per square inch​ (psi) of a certain type of concrete. Complete parts​ (a) through​ (f) below. ​7-Day Strength​ (psi), x 2480 3330 2620 3380 3390 ​28-Day Strength​ (psi), y 4120 4850 4190 5020 5220 ​(a) Treating the​ 7-day strength as the explanatory​ variable, x, use technology to determine the estimates of beta 0 and beta 1. beta 0almost equalsb 0equals nothing ​(Round to one decimal place as​ needed.) beta 1almost equalsb 1equals nothing ​(Round to four decimal places as​ needed.) Estimate error? P value? Upper? Lower?

Answer 1

linear regression model using Minitab:

• Click Stat → Regression → Regression → Fit Regression Model
• A new window named “Regression” pops up.
• Select “'28 Day Strenth'” as “Response” and “'7 Day Strenth'” as “Predictor.”

• Click “OK” in the window named “Regression.”
• Resul:

From the Minitab output:

1.

=1411 + 1.075 x

2.

95% Confidence interval :

Upper:1.535

Lower:0.616

3.

P-value 0.005

4.

Estimate Error = S=130.133

Hope this will be helpful. Thanks and God Bless You :)