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Use the given cost table for the same product from two different companies to create a linear system.

Then solve the system to determine when the cost of the product will be the same and what the price will
be.
Let f(x) represent the cost for dry cleaning at Company 1 and let g(x) represent the cost of dry cleaning
at Company 2, where x is the number of garments dry cleaned.
Number of Garments
Company 1
Company 2
5
$117.75
$51.75
5
10
$138.50
$83.50
15
$159.25
$115.25
f(x) =
+
(96)=
X +
If 1 P
Both Company 1 and Company 2 charge $
for cleaning
garments.
X1 =

Use the given cost table for the same product from two different companies to create-example-1
User Wayne Weibel
by
2.9k points

1 Answer

19 votes
19 votes

Answer:

Explanation:

Calculate the slope for both companies (1 and 2) by picking two points from the table for each company and then determine the "Rise/Run."

The costs for both companies:

Cost ($)

Shirts 1 f(x) 2 g(x)

5 117.75 51.75

15 159.25 115.25

Rise 41.5 51.75

Run 10 10

Rise/Run 4.15 6.35

The slopes of these lines are 4.15 and 6.35

Comp. 1: y = 4.15x + b

Comp. 2: y = 6.35x + b

Strangely, both equations have a b that is not zero. This means that, mathematically, there is a cost for doing 0 shirts. Only in America.

One can see this issue by looking at the difference in cost for the first 5 shirts compared to the second set of 5. For Company 1, the first 5 is $117.75, but the second 5 brings us to only a total of $138.50 - a difference of only $20.75. Same with Company 2. The first 5 shirts costs much more than the second five. The third set of 5 shirts (10 - 15) is consistent with the increase with the second set (5-10).

While this doesn't make sense, we must assume there is an initial starting charge, which will be the value of b in the y=mx+b format.

Top calculate b in both equations, enter one of the data points (e.g., (5,117.8) for company 1, and (5,51.75) for company 2 and solve each equation for b.

The results will given these equations:

Company 1: f(x) = 4.15x + 97, and

Company 2: g(x) = 6.35x + 20

Take one shirt into company 1 and you're out $97 before paying for the one laundered shirt. $20 for Company 2.

But each company has a different shirt price:

Company 1: $4.15/shirt

Company 2: $6.35/shirt

We can find the point at which both companies charge the same for x number of shirts by setting the equations equal to each other [i.e., their costs are the same] and solving for x:

4.15x + + 97 = 6.35x + 20

x = 35 shirts

At 35 shirts, both companies will charge $242.30

We can also graph the two equations to find their intersection (both have the same cost). The graph also highlights the absurdity of interpreting anything under 1 shirt. So the range of the functions is x ≥ 1.

See attachment.

Use the given cost table for the same product from two different companies to create-example-1
User Jetta
by
3.2k points