Question

Suppose that the daily demand (𝐷) for a certain item in the capital market is random and behaves according to a uniform probability (quantity) law with 𝑑 = 0.1, … ,19. Every day, 𝑥 units of the item are brought for sale, which are sold at 5 mu per unit and, if not sold, 2 mu are lost (for storage, return or other). Determine the number of these items, which should be brought at the beginning of the day, so that the expected utility is maximum.

128

likes
641 views

Answer to a math question Suppose that the daily demand (𝐷) for a certain item in the capital market is random and behaves according to a uniform probability (quantity) law with 𝑑 = 0.1, … ,19. Every day, 𝑥 units of the item are brought for sale, which are sold at 5 mu per unit and, if not sold, 2 mu are lost (for storage, return or other). Determine the number of these items, which should be brought at the beginning of the day, so that the expected utility is maximum.

Expert avatar
Murray
4.5
92 Answers
\text{Expected Profit} = \frac{\int_{0.1}^{19} \left[ \min(5x, 7D - 2x) \right] \, dD}{19 - 0.1}

Since there's a uniform distribution, we consider the two cases where the profit equations exist:

1. **Demand \( D \geq x \) :**

\text{Profit} = 5x

2. **Demand \( D < x \) :**

\text{Profit} = 7D - 2x

Integrate over both segments accordingly:

E[\text{Profit}] = \int_{0.1}^{x} \left( 7D - 2x \right) \frac{dD}{18.9} + \int_{x}^{19} 5x \frac{dD}{18.9}

Solve these integrals:

E[\text{Profit}] = \left( \frac{7}{18.9} \int_{0.1}^{x} D \, dD - \frac{2x}{18.9} \int_{0.1}^{x} dD \right) + \frac{5x}{18.9} \int_{x}^{19} dD

= \frac{7}{18.9} \cdot \left[ \frac{D^2}{2} \right]_{0.1}^{x} - \frac{2x}{18.9} \left[ D \right]_{0.1}^{x} + \frac{5x}{18.9} \left[ D \right]_{x}^{19}

Evaluating these:

1. First part:

= \frac{7}{18.9} \left( \frac{x^2}{2} - \frac{0.1^2}{2} \right) - \frac{2x}{18.9} (x - 0.1)

2. Second part:

= \frac{5x}{18.9} (19 - x)

Combine and simplify:

E[\text{Profit}] = \frac{7x^2 - 7 \cdot 0.01}{2 \times 18.9} - \frac{2x^2 - 0.2x}{18.9} + \frac{5x (19 - x)}{18.9}

After simplifying, the expected profit equation in terms of \( x \):

E[\text{Profit}] = \frac{(7x^2 - 0.07) - (2x^2 - 0.2x) + 5x(19 - x)}{18.9}

Set the derivative of accumulated profit with respect to \( x \) to 0 and solve for \( x \):

\frac{d}{dx} \left[ \frac{5x (19 - x) + 7 \frac{x^2}{2} - 0.07 - 2x^2 + 0.2x}{18.9} \right] = 0

\frac{d}{dx} \left[ \frac{13.6x - \frac{7x^2}{2} - 0.07 - 2x^2 + 0.2x}{18.9} \right] =0

13.6 \quad \text{results in maximum expected profit}

Therefore:

x = 13.6

Frequently asked questions (FAQs)
Question: What is the amplitude, period, phase shift, and range of the function f(x) = sin x?
+
How many different ways can 4 students be seated in a row of 10 chairs?
+
Find the integral of ∫(3x^2 - 5)dx
+
New questions in Mathematics
A=m/2-t isolate t
1 + 1
-6n+5=-13
A normally distributed population has a mean of 118 with a standard deviation of 18. What score separates the lowest 72% of the distribution from the rest of the scores?
Let X be a discrete random variable with range {1, 3, 5} and whose probability function is f(x) = P(X = x). If it is known that P(X = 1) = 0.1 and P(X = 3) = 0.3. What is the value of P(X = 5)?
By differentiating the function f(x)=(x³−6x)⁷ we will obtain
Suppose 50% of the doctors and hospital are surgeons if a sample of 576 doctors is selected what is the probability that the sample proportion of surgeons will be greater than 55% round your answer to four decimal places
(2x+5)^3+(x-3)(x+3)
7/6-(-1/9)
2x+4x=
find f(x) for f'(x)=3x+7
suppose random variable x follows poisson distribution with expected value 3. what is variance of x?
A storage maker price is $2.50 per square feet. Find the price of a custom shed 4 yards long, and 5yards wide and 8 feet tall
1. A capital of $3,831 was lent, and it has produced interest of $840 from 05-12-2022 to 1-12-2023. At what annual simple interest rate was the capital lent?
-1%2F2x-4%3D18
For what values of m is point P (m, 1 - 2m) in the 2⁰ quadrant?
Find the zero of the linear function 8x + 24 = 0
X^X =49 X=?
A group of 17 people spent 9 days on vacation and spent R$776.34 on barbecue meat and the bill needs to be divided as follows: 6 people stayed for 9 days, 7 people stayed for 4 days, and 2 people stayed for 5 days and 2 people stayed 3 days, how much does each group have to pay for the days they stayed?
The perimeter of a rectangular rug is 42 feet. The width is 9 feet. What is the length?