We start to solve this by looking for the formula that let us calculate an average value, this formula would be:

where Save is the average score and s is the score of each exam, Since we know the value of the score Save and 4 of the exams we can replace them in the formula, like this:
And we can solve for s5, which is the score that we need to find, like this:

Then, Pedro must have a 55 score on the fifth test
Divide o.946 by 7 that's your awnser.
For this problem, here’s how you do it.
To solve the area of a cylinder, you need to do steps.
Calculate volume of a cylinder: V = πr2h.
...
Calculate the lateral surface area of a cylinder (just the curved outside)**: L = 2πrh.
...
Calculate the top and bottom surface area of a cylinder (2 circles): T = B = πr. ...
Total surface area of a closed cylinder is:
439.82 square inches
Marginal profit, P(x) = R(x) - C(x)
P(x) = x³ - 5x² + 7x + 10
x³ - 5x² + 7x + 10 = 0
If you solve it, you get x = -0.839 where P(x) is zero