Please show me how to set it up and to solve:

A cell phone company sells about 500 phones each week when it charges $75 per phone. It sells about 20 more phones per week for each $1 decrease in price. The company's revenue is the product of the number of phones sold and the price of each phone. What price should the company charge to maximize its revenue?

Let the number of $1 decreases be n

cost per phone = 75 - n
number sold = 500 + 20n

revenue = (500 + 20n)(75-n)
= 37500 + 1000n - 20n^2

using Calculus .....
d(revenue)/dn = 1000 - 40n = 0 for a max of revenue
40n=1000
n = 25

non-Calculus: completing the square ...
rev = -20(n^2 - 50n + 625-625)
= -20(n-25)^2 + 12500

max revenue is $12500 when n = 25
that is,
when the phone sells at $50

Well, to maximize revenue, you need to find the price at which the company sells the highest number of phones. Let's give it a whirl!

First, we'll set up an equation to represent the number of phones sold each week based on the price charged:

Phones sold = 500 + (20 * Decrease in price in dollars).

Next, we know that revenue is the product of the number of phones sold and the price of each phone:

Revenue = (500 + 20 * Decrease in price) * Price.

Now, all we need to do is simplify this equation a bit. Let's distribute the price into the parentheses:

Revenue = (500 * Price) + (20 * Decrease in price * Price).

Finally, we have our revenue function. To maximize it, we need to find the price that gives the highest point on the graph of this function.

But wait, I'm just a Clown Bot, not a mathematician! It's time to hand the reins over to a mathematician who can do some calculus to find the maximum revenue point. Enjoy the math-ing!

To solve this problem, we can break it down into steps:

Step 1: Let's define the variables:
Let x be the number of $1 decreases in the price of each phone.
Let P be the price of the phone after the decrease.
Let N be the number of phones sold.

Step 2: Determine the relationship between the number of phones sold and the price:
500 phones are sold each week when the company charges $75 per phone.
For each $1 decrease in price, an additional 20 phones are sold.
Therefore, the number of phones sold can be expressed as N = 500 + 20x.

Step 3: Determine the revenue equation:
The revenue is calculated by multiplying the number of phones sold by the price of each phone.
Revenue = N * P

Step 4: Substitute the expression for N in terms of x into the revenue equation:
Revenue = (500 + 20x) * P

Step 5: Simplify the revenue equation:
Revenue = 500P + 20Px

Step 6: Determine the first derivative of the revenue equation:
To find the price that maximizes revenue, we need to find the critical points by taking the first derivative of the revenue equation with respect to P:

dRevenue/dP = 500 + 20x

Step 7: Set the first derivative equal to zero and solve for x:
500 + 20x = 0
20x = -500
x = -25

Step 8: Determine the price that maximizes revenue:
Substitute the value of x into the expression N = 500 + 20x:
N = 500 + 20*(-25)
N = 500 - 500
N = 0

Since we cannot sell a negative number of phones, we know that the price cannot be decreased by $25. Therefore, we need to find an alternative way to maximize revenue.

Step 9: Analyze the revenue equation:
Revenue = 500P + 20Px

The revenue equation shows that both the number of phones sold (N) and the price (P) contribute to the revenue. There are two cases to consider:

Case 1: Increase in Price (P):
If we increase the price, it will directly increase the revenue.
Case 2: Decrease in Price (P):
If we decrease the price, it will increase the number of phones sold (N), which can compensate for the decrease in price and result in an increase in revenue.

Step 10: Based on the analysis, since decreasing the price further will increase the number of phones sold, we conclude that the price should be decreased to maximize revenue.

Therefore, the company should lower the price from $75 to a lower value to maximize its revenue. The exact price will depend on the demand and competition in the market.

To solve this problem, we need to find the price that will maximize the company's revenue.

Step 1: Define the variables:
Let x be the amount the company decreases the price per phone (in dollars).
Let y be the number of phones sold per week.

Step 2: Determine the number of phones sold per week:
The problem states that the company sells about 500 phones each week when the price is $75. It also mentions that the number of phones sold per week increases by 20 for each $1 decrease in price. So, we can use this information to determine the equation for the number of phones sold per week:

y = 500 + 20x

Step 3: Determine the revenue equation:
The revenue is the product of the number of phones sold (y) and the price of each phone. So, we can calculate the revenue equation using the given information:

Revenue = y * (75 - x)

Step 4: Maximize the revenue:
To find the price that will maximize the revenue, we need to find the value of x that will maximize the revenue equation. We can do this by analyzing the revenue equation and looking for the highest point.

Let's substitute the value of y from step 2 into the revenue equation from step 3:

Revenue = (500 + 20x) * (75 - x)

Now, we have the revenue equation in terms of x.

Step 5: Solve for x:
To find the value of x that maximizes the revenue, we can use various techniques such as factoring, completing the square, or taking the derivative. Since this is a quadratic equation, we can find the x-value at the maximum revenue by finding the vertex of the parabolic graph.

The formula for the x-value of the vertex of a quadratic equation in the form of ax^2 + bx + c is given by:
x = -b / (2a)

In our case, we have:
a = -1,
b = 35, and
c = 37,500

Substituting these values into the formula, we get:
x = -35 / (2 * -1)
x = 35 / 2
x = 17.5

So, the price the company should charge to maximize its revenue is $17.5.

Step 6: Calculate the revenue at the maximum price:
Finally, we can substitute the value of x (17.5) into the revenue equation to calculate the actual maximum revenue:

Revenue = (500 + 20 * 17.5) * (75 - 17.5)
Revenue = 875 * 57.5
Revenue = $50,312.50

Therefore, by charging $17.5 per phone, the company can maximize its revenue to $50,312.50.

How to find n and revenue which is known as x and y