Answer: 28
Step-by-step explanation:
Given
Kenny made 7 serves over the net for every 2 serves that did not go over the net i.e. success rate of Kenny is
for 36 serves, applying the same success rate, it is
Serves that did not make over the net is
Thus, Kenny will make 28 serves that make over the net
Answer:
26 ft square by 13 ft high
Step-by-step explanation:
The tank will have minimum surface area when opposite sides have the same total area as the square bottom. That is, their height is half their width. This makes the tank half a cube. Said cube would have a volume of ...
2·(8788 ft^3) = (26 ft)^3
The square bottom of the tank is 26 ft square, and its height is 13 ft.
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<em>Solution using derivatives</em>
If x is the side length of the square bottom, the height is 8788/x^2 and the area is ...
x^2 + 4x(8788/x^2) = x^2 +35152/x
The derivative of this is zero when area is minimized:
2x -35152/x^2 = 0
x^3 = 17576 = 26^3 . . . . . multiply by x^2/2, add 17576
x = 26
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As the attached graph shows, a graphing calculator can also provide the solution.
We can set this problem up as an algebraic equation, which we can then solve to find our answer.
We start at -3. So we can start our equation with that:
However, this doesn't represent any change in temperature, just that we start at -3. To show change, we will use the variable , where
stands for the number of hours. Each hour accounts for a change of -2.5 in degrees, meaning that we must multiply our
by -2.5. We can now add this term into our equation:
We are trying to find when we will reach -18 degrees, so we will set our entire equation equal to -18 and solve:
It will take us 6 hours, or choice A.