First, we determine the volumes of the posts may it be cylindrical in shape or rectangular prism.
(A) cylindrical:
( π(26.7/100)² - π(24.2/100)²)*(7.5) = 0.3 m³
(B) rectangular prism:
(40/100)²(7.5) - (35/100)²(7.5) = 0.28125 m³
Then, we calculate for the amount of substance
(A) cylindrical: (0.3 m³)(2700 kg/m³) = 810 kg
(B) rectangular prism : (0.28125 m³)(2700 kg/m³) = 759.375 kg
Then, calculate for the costs
(A) (810 kg)($0.38/kg) = $307.8
(B) (759.375 kg)($0.38/kg) = $288.56
Thus, the answer for A is rectangular post
B. About $19.24 can be saved.
Answer:
divide
Step-by-step explanation:
You haven't told me what the question is. But I put the mouse
to my forehead, closed my eyes, took a deep breath, and I could
see it shimmering in my mind's eye. It was quite fuzzy, but I think
the question is
"What score does Andrew need on the next test
in order to raise his average to 72% ?"
The whole experience drew an incredible amount of energy
out of me, and the mouse is a total wreck. So we'll just go ahead
and answer that one. I hope it's the correct question.
The average score on 4 tests is
(1/4) (the sum of all the scores) .
In order for Andrew to have a 72% average on 4 tests,
the sum of the 4 scores must be
(4) x (72%) = 288% .
Out of that total that he needs, he already has
(64% + 69% + 73%) = 206%
on the first three tests.
So in order to average 72% for all 4 tests,
he'll need to score
(288% - 206%) = 82%
on the fourth one.
The answer would be 28 feet, to get area you do length times width, 7 x 4 = 28