<span>30 hours
For this problem, going to assume that the actual flow rate for both pipes is constant for the entire duration of either filling or emptying the pool. The pipe to fill the pool I'll consider to have a value of 1/12 while the drain that empties the pool will have a value of 1/20. With those values, the equation that expresses how many hour it will take to fill the pool while the drain is open becomes:
X(1/12 - 1/20) = 1
Now solve for X
X(5/60 - 3/60) = 1
X(2/60) = 1
X(1/30) = 1
X/30 = 1
X = 30
To check the answer, let's see how much water would have been added over 30 hours.
30/12 = 2.5
So 2 and a half pools worth of water would have been added. Now how much would be removed?
30/20 = 1.5
And 1 and half pools worth would have been removed. So the amount left in the pool is
2.5 - 1.5 = 1
And that's exactly the amount needed.</span>
You have to add all the scores and dived by the 20 students, the result is 65.85%
Answer:
20
Step-by-step explanation:
25*4 equals 100 so 80/4 is 20.
The point-slope form the line which has the value of slope -5 and contains a point as A(2,-1) is (y+1)=-5(x-2).
<h3>What is point slope form?</h3>
The point slope form of a line is the expression of line which has a specified slope and passes through a point.
The point slope form is givne as,
(y-y₁)=m(x-x₁)
Here, m is the slope of the line, x₁ is the x coordinate of the point by which line passes and y₁ is the y coordinate of the same point.
The slope of a line is -5. This line contains the point A (2,-1). Thus, the point slope form is,
(y-y₁)=m(x-x₁)
(y-(-1))=-5(x-2)
(y+1)=-5(x-2)
Thus, the point-slope form the line which has the value of slope -5 and contains a point as A(2,-1) is (y+1)=-5(x-2).
Learn more about the point slope form here;
brainly.com/question/6497976
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