Answer:
i think the answer is 38 because u first answer 4x5 and then 7x7 and then 3x5 and hlthen u subtract 20 from 15 and then u add 5 and 42 and then when u get ur answer of 47 u subtract 9
The function in variable w giving the cost C (in dollars) of constructing the box is C(w) = 30w² + 270/w. The result is obtained by using the formula of volume and area of the box.
<h3>How to determine the function?</h3>
We have a rectangular storage container without a lid.
- Volume, V = 10 m³
- Length, l = 2w
- Width, w = w
- Base costs $15/m²
- Sides costs $9/m²
The formula of volume of the box is
V = l × w × h
Where
- l = length
- w = width
- h = height
So, the height is
10 = 2w × w × h
10 = 2w² × h
h = 10/2w²
h = 5/w²
To find the total cost, calculate the area of base and sides of the box!
See the picture in the attachment!
The base area is
A₁ = 2w × w = 2w² m²
The sides area is
A₂ = 2(2wh + wh)
A₂ = 2(3wh)
A₂ = 6wh
A₂ = 6w(5/w²)
A₂ = 30/w m²
The total cost is
C = $15(2w²) + $9(30/w)
C = $30w² + $270/w
The function of the total cost is
C(w) = 30w² + 270/w
Hence, the function of constructing the box is C(w) = 30w² + 270/w.
Learn more about function of area here:
brainly.com/question/28698395
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Answer:
96 marks
Step-by-step explanation:
We know that the mean of a given amount of values is the sum of the values divided by the number of values
Let the marks in the fourth test = x marks
Mean of the values = 90
(85 + 90 + 89 + x) / 4 = 90
264 + x = 360
x = 96
Therefore, Jamie needs 96 marks in her 4th test to get a mean score of 90
The volume is equal to 134.041