Answer:
$9327
Step-by-step explanation:
Apparently, the cost function is supposed to be ...
C(x) = 0.4x^2 -112x +17167
This can be rewritten to vertex form as ...
C(x) = 0.4(x^2 -280) +17167
C(x) = 0.4(x -140)^2 +17167 -0.4(19600)
C(x) = 0.4(x -140)^2 +9327
The vertex of the cost function is ...
(x, C(x)) = (140, 9327)
The minimum unit cost is $9327.
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<em>Comment on the question</em>
You found the number of units that result in minimum cost (140 units), but you have to evaluate C(140) to find the minimum unit cost.
Answer:
Talking 65 minutes, $ 6.50 must be paid.
Step-by-step explanation:
Since your cell phone plan is by the minute, and each minute of use cost $ 0.10, to create a relation that represents the amount spent, A, per minute, m, of call time, and then use the relation to find the amount spent if you talk 65 minutes, the following calculations must be performed:
0.10 x M = A
0.10 x 65 = A
6.50 = A
Thus, talking 65 minutes, $ 6.50 must be paid.
For this case, the first thing to do is to observe that the figure is symmetrical with respect to the FH axis.
Therefore, the following lengths are the same:

So, by equalizing both sides we have:

From here, we clear the value of m.
We have then:


Answer:
The value of m is given by:

The number is less than 190,000 and greater than 180,000
5,000 more than the number has 187 thousands
2000 less than the number has 4 hundreds
180, 000 <n> 190, 000
180,000 + 2000 = n = 5000-187, 000
182,000 = n = 182, 000
Or,
180, 000 <n> 190,000
n + 5000= 187, 000 n – 2000 = 180, 000
n= 187, 000- 5000 n = 180, 000 + 2000
n= 182, 000 n= 182, 000
5/12 because 1/1 is a whole, 1, so all you have to do is 1 - 7/12.