When the condition has
been given as 1000 share with cost 8.6 Yuan and price 30 Yuan the constant and
equation will be completed which is exhibited below. The quantity is 2,020 in
maximum profit and the maximum profit is 40,820 Yuan according to the modelling
equation. 100~1100 and 100~3600 is defined as below Figure 1-6 to discuss in
detail. The former is actual condition and the latter is the predicted. They
are fit well to modelling equation. The coefficient a and b & a, b, c has
been solved according to the modelling equation discussed as below. In this
study TR is total revenue; TC is total cost; MR is marginal revenue; AR is average revenue; PR is profit; MC is
marginal cost; Q is quantity (Figure 1-3).
The TR increases when Q increases. TR changes
from 3,000 Yuan to 40,000 Yuan when Q becomes from 100 to 1100. Meantime AR
decreases from 28 Yuan to 36 Yuan when Q becomes the same. At last MR maintains
32~42 Yuan. MC is the same value to MR. from Figure 1 it is known that PR and
TC will increase when the Q increases. The PR changes from 2,000 Yuan to 32,000
Yuan when Q is from 100 to 1000 and TC becomes from 1,000 to 7,500 Yuan when Q
becomes from 100 to 1100. Figure 3 shows that the TC decreases from 0 Yuan to
5,000 Yuan according to Q from 0 to 1750. Figure 4 shows when the Q scope is
100~3600 the TR will increase from 500 Yuan to 170,000 Yuan and AR will
decrease. Figure 4 shows TC is parabolic which maximum is 170,000 Yuan with
Q=3600 meantime the PR increase from 0 to 180,000 Yuan with Q from 0 to 3600.
There is MR=MC in terms of Q the same (Figure 4-6).

Figure 1: The graph of Pr and TC
& Q=100~1100.

Figure 2: The graph of TR, AR?MR
and MC & Q=100~1100

Figure 3: The graph of PR and TC,
Q=100~3600.

Figure 4: The graph of TR, MR, AR
and MC & Q=100~3600.

Figure 5: The graph of TR, TC, PR,
MR &AR and Q=100~1000.

Figure 6: The graph of TR, TC, PR,
MR &AR and Q=100~3600.
The modelling of maximum
profit and it’s quantity in this study has been built as following. To suppose
the product demand function as
(1)
It has
(2)
(3)
To suppose the total cost
function as
(4)
It has
(5)
And
(6)
So
(7)
Here P is the demand, Q is quantity, TC is cost,
a?b &a?b?c is the coefficient. The Figure 5 and 6 shows that the
relationship between TR, TC, PR, MR & AR and Q with the part of 0~1000 and
0~3600. It is known that when Q=1750 the TC will be 5,000 Yuan which is the
highest result here. The extension curve TC, TR & PR?will have summit at Q=3,500 with 170,000 Yuan &180,000 Yuan
respectively It is known that the relationship of PR=TR-TC in the curves.