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to arrive at 2000 liters of 60% saline solution the attendant has to mix a 90% and a 40% saline solution. How many liters of eac

CaHeK987 [17]

Answer:

800 liters of 90% saline solution and 1200 liters of 40% saline solution should be used.

Step-by-step explanation:

Given:

At 2000 liters of 60% saline solution the attendant has to mix a 90% and a 40% saline solution.

Now, to find the number of liters of saline solution each should be used.

Let the liters of 90% saline solution mix be $x.$

And let the liters of 40% saline solution mix be $y.$

So, the total number of liters:

$x+y=2000.$

$y=2000-x\ \ \ ....(1)$

Now, the total percentage of saline solution:

$90\%\ of\ x+40\%\ of\ y=60\%\ of\ 2000$

$\frac{90}{100}\times x+\frac{40}{100}\times y=\frac{60}{100}\times 2000$

$0.9x+0.4y=1200$

Substituting the value of $y$ from equation (1) we get:

$0.9x+0.4(2000-x)=1200$

$0.9x+800-0.4x=1200$

$0.5x+800=1200$

Subtracting both sides by 800 we get:

$0.5x=400$

Dividing both sides by 0.5 we get:

$x=800.$

The liters of 90% saline solution mix = 800.

Now, substituting the value of $x$ in equation (1) to get the liters of 40% saline solution:

$y=2000-x$

$y=2000-800$

$y=1200.$

Thus, the liters of 40% saline solution = 1200.

Therefore, 800 liters of 90% saline solution and 1200 liters of 40% saline solution should be used.

8 0

3 years ago

A company manufactures and sells x television sets per month. The monthly cost and price-demand equations are C(x)equals72 com

solmaris [256]

Answer:

Part (A)

1. Maximum revenue: $450,000

Part (B)

2. Maximum protit: $192,500

3. Production level: 2,300 television sets

4. Price: $185 per television set

Part (C)

5. Number of sets: 2,260 television sets.

6. Maximum profit: $183,800

7. Price: $187 per television set.

Explanation:

0. Write the monthly cost and price-demand equations correctly:

Cost:

$C(x)=72,000+70x$

Price-demand:

$p(x)=300-\dfrac{x}{20}$

Domain:

$0\leq x\leq 6000$

1. Part (A) Find the maximum revenue

Revenue = price × quantity

Revenue = R(x)

$R(x)=\bigg(300-\dfrac{x}{20}\bigg)\cdot x$

Simplify

$R(x)=300x-\dfrac{x^2}{20}$

A local maximum (or minimum) is reached when the first derivative, R'(x), equals 0.

$R'(x)=300-\dfrac{x}{10}$

Solve for R'(x)=0

$300-\dfrac{x}{10}=0$

$3000-x=0\\\\x=3000$

Is this a maximum or a minimum? Since the coefficient of the quadratic term of R(x) is negative, it is a parabola that opens downward, meaning that its vertex is a maximum.

Hence, the maximum revenue is obtained when the production level is 3,000 units.

And it is calculated by subsituting x = 3,000 in the equation for R(x):

R(3,000) = 300(3,000) - (3000)² / 20 = $450,000

Hence, the maximum revenue is $450,000

2. Part (B) Find the maximum profit, the production level that will realize the maximum profit, and the price the company should charge for each television set. 

i) Profit(x) = Revenue(x) - Cost(x)

Profit (x) = R(x) - C(x)

$Profit(x)=300x-\dfrac{x^2}{20}-\big(72,000+70x\big)$

$Profit(x)=230x-\dfrac{x^2}{20}-72,000\\\\\\Profit(x)=-\dfrac{x^2}{20}+230x-72,000$

ii) Find the first derivative and equal to 0 (it will be a maximum because the quadratic function is a parabola that opens downward)

Profit' (x) = -x/10 + 230

-x/10 + 230 = 0

-x + 2,300 = 0

x = 2,300

Thus, the production level that will realize the maximum profit is 2,300 units.

iii) Find the maximum profit.

You must substitute x = 2,300 into the equation for the profit:

Profit(2,300) = - (2,300)²/20 + 230(2,300) - 72,000 = 192,500

Hence, the maximum profit is $192,500

iv) Find the price the company should charge for each television set:

Use the price-demand equation:

p(x) = 300 - x/20

p(2,300) = 300 - 2,300 / 20

p(2,300) = 185

Therefore, the company should charge a price os $185 for every television set.

3. Part (C) If the government decides to tax the company $4 for each set it produces, how many sets should the company manufacture each month to maximize its profit? What is the maximum profit? What should the company charge for each set?

i) Now you must subtract the $4 tax for each television set, this is 4x from the profit equation.

The new profit equation will be:

Profit(x) = -x² / 20 + 230x - 4x - 72,000

Profit(x) = -x² / 20 + 226x - 72,000

ii) Find the first derivative and make it equal to 0:

Profit'(x) = -x/10 + 226 = 0

-x/10 + 226 = 0

-x + 2,260 = 0

x = 2,260

Then, the new maximum profit is reached when the production level is 2,260 units.

iii) Find the maximum profit by substituting x = 2,260 into the profit equation:

Profit (2,260) = -(2,260)² / 20 + 226(2,260) - 72,000

Profit (2,260) = 183,800

Hence, the maximum profit, if the government decides to tax the company $4 for each set it produces would be $183,800

iv) Find the price the company should charge for each set.

Substitute the number of units, 2,260, into the equation for the price:

p(2,260) = 300 - 2,260/20

p(2,260) = 187.

That is, the company should charge $187 per television set.

7 0

3 years ago

A necklace regularly sells for $18.00. the store advertises a 15% discount. what is the sale price of the necklace in dollars

SSSSS [86.1K]

I can solve with 2 methods:

I. Because the discount is 15 % of 18 $ , the price will be (100-15=85) 85 % of 18 $
18*85/100= 15,3 $ ( the sale price)

II. The discount is 15 % of 18$
15*18/100= 2,7$ ( the discount)
then I decrease it from the regularly price
18$-2,7$=15,3 $ (the sale price)

Personally I believe the first is an easier method.
I hope you understand and you can apply this in every similary problem.

6 0

3 years ago

Find the number of rooms per hour that Jake, Lionel, and Donald can paint working together if t is 6 hours.

lara31 [8.8K]

You dont have a complete question

7 0

3 years ago

On the first circle, what segment is a diameter? How long is it?

stiv31 [10]

Answer:

The segment that is the diameter is EB

It is 8 cm long

Step-by-step explanation:

6 0

3 years ago