A.) R(20) = -10(20)^2 + 800(20) = -10(400) + 16000 = -4000 + 16000 = $12,000
R(25) = -10(25)^2 + 800(25) = -10(625) + 20000 = -6250 + 20000 = $13,750
R(30) = -10(30)^2 + 800(30) = -10(900) + 24000 = -9000 + 24000 = $15,000
b.) For maximum revenue, dR/dp = 0
dR/dp = -20p + 800 = 0
20p = 800
p = 40
Therefore, the maximum revenue will be recorded when the price is set at $40.
<h3>
Answer: Choice C) 421.9</h3>
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Explanation:
You're on the right track. You wrote down the proper expression to get the final answer, assuming you meant to write 75/4 as the third term inside the parenthesis. This works because each time you cut the side length in half to get each smaller triangle's side. The 3 is because there are 3 sides for each of the triangles. Much of this I have a feeling you already know as you wrote down the expression on the page, though I'm not 100% sure of your mindset. Computing this expression leads to 421.875 which rounds to 421.9
note: an alternative is to write 3*75 + 3*75/2 + 3*75/4 + 3*75/8, though that is more work. It's better to have that 3 factored out.
Answer:
Correct choice is B
Step-by-step explanation:
In step 4 were proved that 
By definition, similar triangles have proportional lengths of corresponding sides. To the side AB corresponds side ED, to the side AC corresponds side DC and to the side BC corresponds side EC. Thus,

Answer:
There are 8 boys for every 10 girls. This is 6 equal groups. Equal ratio
Step-by-step explanation: