Ryan Parks Thanks for your help with my previous question on

Ryan Parks,

Thanks for your help with my previous question on 7/21. Below is the data I used. I am not able to get the same regression summary output as your regression analysis below of the cubic formula.   What am I doing wrong with column Q^3? I am taking 100 ^3 = 1000000, 400^3 =64000000.... What was your data for Cubic^3?

Quantity                       Total Cost       

10                               104

20                     107

30                     109

40                     111.5

50                     114.5

60                     118

70                     123

80                     128.5

90                     137

100                   150

Q^2                Q^3                

100                 1000000                       

400                 64000000                     

900                 729000000                   

1600                4096000000                  

2500                15625000000                

3600               46656000000                

4900                1.17649E+11                

6400               2.62144E+11                

8100                5.31E+11                     

10000              1.00E+12                     

Solution

The way Q^3 is obtained is wrong. What you are taking Q^3 is actually Q^6, and this is because you are taking cube of Q^2, and hence your regression analysis results are all wrong. The write values of Q^3 are given below: