Refer to the diagram shown below.
The volume of the container is 10 m³, therefore
x*2x*h = 10
2x²h = 10
h = 5/x² (1)
The base area is 2x² m².
The cost is $10 per m², therefore the cost of the base is
(2x²)*($10) = 20x²
The area of the sides is
2hx + 2(2xh) = 6hx = 6x*(5/x²) = 30/x m²
The cost is $6 per m², therefore the cost of the sides is
(30/x)*($6) = 180/x
The total cost is
C = 20x² + 180/x
The minimum cost is determined by C' = 0.
That is,
40x - 180/x² = 0
x³ = 180/40 = 4.5
x = 1.651
The second derivative of C is
C'' = 40 + 360/x³
C''(1.651) = 120 >0, so x = 1.651 m yields the minimum cost.
The total cost is
C = 20(1.651)² + 180/1.651 = $163.54
Answer: $163.54
Let n = number of records.
Each record costs $7, so n records cost 7n.
She then spent $3, so the total spent is 3n + 3.
She spent a total of $24, so 3n + 3 must equal 24. That gives us the following equation.
7n + 3 = 24
Subtract 3 from both sides.
7n = 21
Divide both sides by 7.
n = 3
Answer: She bought 3 records.
Answer:multiply
Step-by-step explanation:6x4 but i aint sure tho
Answer: its 2.50 so B
Step-by-step explanation: I just did the test
Answer:
9
Step-by-step explanation:
You take 12 and subtract 8. You should get 4. Then you divide 36 by 4 and you get 9. So, 12 - 8 x 4 = 36.