Answer:
The value of the test statistic is 
Step-by-step explanation:
The null hypothesis is:
The alternate hypotesis is:
Our test statistic is:
In which X is the sample mean, 
is the null hypothesis value, 
is the standard deviation and n is the size of the sample.
In this problem:
So
The value of the test statistic is
Capacity of the pool = 30 x 20 x 5 = 3000 ft³
Amount of water already filled = 30 x 20 x 4 = 2400 ft²
Amount of water needed to full the pool = 3000 - 2400 = 600 ft²
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Answer: 600 ft² of water is needed to fill up the pool.
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Answer:
Bc = √63 ft
Step-by-step explanation:
Here, we want to get the length of BC
As we can see, there is a right angled triangle ABC, with 12ft being the hypotenuse and 9 ft the other side
So we want to get the third leg which is BC
we can use the Pythagoras’ theorem here
And that states that the square of the hypotenuse equals the sum of the squares of the two other sides
let the missing length be x
12^2 = x^2 + 9^2
144 = x^2 + 81
x^2 = 144-81
x^2 = 63
x = √63 ft
