The cost, in dollars, to produce [tex]\( x \)[/tex] vats of ice cream is [tex]\( C(x) = 4x + 2 \)[/tex]. When selling them to ice cream shops, the price-demand function, in dollars per vat, is [tex]\( p(x) = 108 - 4x \)[/tex].

1. Find the profit function:
[tex]\[ P(x) = \][/tex]

2. How many vats of ice cream need to be sold to maximize the profit?
[tex]\[ \square \][/tex]

3. Find the maximum profit:
[tex]\[ \square \][/tex]

4. Find the price to charge per vat to maximize profit:
[tex]\[ \square \][/tex]



Answer :

To find the solutions to the given problem, follow these steps:

### Step 1: Define Profit Function

The profit function, [tex]\(P(x)\)[/tex], is given by the difference between the Revenue [tex]\(R(x)\)[/tex] and the Cost [tex]\(C(x)\)[/tex].

1. Revenue, [tex]\(R(x)\)[/tex]: The revenue is calculated as the number of vats sold multiplied by the price per vat.
[tex]\[ R(x) = x \cdot p(x) = x \cdot (108 - 4x) = 108x - 4x^2 \][/tex]

2. Cost, [tex]\(C(x)\)[/tex]: The cost function is given as:
[tex]\[ C(x) = 4x + 2 \][/tex]

3. Profit, [tex]\(P(x)\)[/tex]: The profit is the revenue minus the cost:
[tex]\[ P(x) = R(x) - C(x) = (108x - 4x^2) - (4x + 2) \][/tex]
Simplifying this, we get:
[tex]\[ P(x) = -4x^2 + 104x - 2 \][/tex]

### Step 2: Find the Number of Vats to Maximize Profit

To find the number of vats, [tex]\(x\)[/tex], that maximizes the profit, we need to find the critical points of [tex]\(P(x)\)[/tex]. This is done by taking the derivative of [tex]\(P(x)\)[/tex] with respect to [tex]\(x\)[/tex] and setting it to zero.

1. Derivative, [tex]\(P'(x)\)[/tex]:
[tex]\[ P'(x) = \frac{d}{dx}(-4x^2 + 104x - 2) = -8x + 104 \][/tex]
Setting the derivative equal to zero to find the critical points:
[tex]\[ -8x + 104 = 0 \][/tex]
Solving for [tex]\(x\)[/tex]:
[tex]\[ x = \frac{104}{8} = 13 \][/tex]
So, 13 vats of ice cream need to be sold to maximize the profit.

### Step 3: Find the Maximum Profit

To find the maximum profit, substitute [tex]\(x = 13\)[/tex] into the profit function [tex]\(P(x)\)[/tex].
[tex]\[ P(13) = -4(13)^2 + 104(13) - 2 \][/tex]
Calculating this, we get:
[tex]\[ P(13) = -4(169) + 1352 - 2 = -676 + 1352 - 2 = 674 \][/tex]
Therefore, the maximum profit is [tex]$674. ### Step 4: Find the Price to Charge Per Vat To find the price to charge per vat to maximize the profit, substitute \(x = 13\) into the price-demand function \(p(x)\): \[ p(13) = 108 - 4(13) \] Calculating this, we get: \[ p(13) = 108 - 52 = 56 \] So, the price to charge per vat to maximize profit is $[/tex]56.

### Summary

- [tex]\(\boxed{P(x) = -4x^2 + 104x - 2}\)[/tex]
- 13 vats of ice cream need to be sold to maximize the profit. [tex]\(\boxed{13}\)[/tex]
- The maximum profit is [tex]$674. \(\boxed{674}\) - The price to charge per vat to maximize the profit is $[/tex]56. [tex]\(\boxed{56}\)[/tex]