I have the answers I just need a simple explanation please :)

a) The data in the table below is plotted on graph paper with the number of pens plotted on the vertical axis.
-----------------------------------------
Number of pen 2 4 6 20
-----------------------------------------
Total money paid($) 20 40 60 200
----------------------------------------

Find the value of the constant K. What is the physical meaning of this constant?

ANS: The constant is 1/10 and the physical meaning is that each pen cost $10.

Question

I have the answers I just need a simple explanation  please :)

a) The data in the table below is plotted on graph paper with the number of pens plotted on the vertical axis. 
-----------------------------------------
Number of pen             2      4      6     20
-----------------------------------------
Total money paid($)   20     40   60     200
----------------------------------------

Find the value of the constant K. What is the physical meaning of this constant?

ANS: The constant is 1/10  and the physical meaning is that each pen cost $10.

aroub · Answer

My question is why is it $10 not 1/10 ?

anonymous · Answer

Your x- axis is in dollars, and your y-axis is in the number of pens.  Your constant K is the slope of the plot, which is loosely speaking the extra amount of "y" you get per change in "x".  It's essentially saying "For one more dollar, I get 1/10th of a pen".  Now of course in real life nobody buys a tenth of a pen, but you can see that paying $1 for 1/10th of a pen is the same as paying $10 for 1 pen.

aroub · Answer

AOOH! okay, thank you :D