
His answer is not correct, when we have a power on the denominator it is dividing and not multiplying, in this case while the expression on the left is being divided the other one is multiplying.
also you could rewrite the expressions like so remembering that powers that are on the denominator can be written as negative powers.
This might be wrong, but you need to get x be itself on the left side and then after you do that, the x on both sides will cancel. Whenever you try to subtract one x from the other it will cancel them. So technically that's all you can do.

So approximately 14.5% of the scores are higher than 600. This means in a sample of 7500, one could expect to see

scores above 600.
Answer:
y = √55
Step-by-step explanation:
All the triangles are similar, so the ratio of short side to hypotenuse is the same for all:
5/y = y/(5+6)
y^2 = 55
y = √55
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<em>Comment on the geometry</em>
There are three "geometric mean" relationships that apply to this geometry.
- the altitude BD is the geometric mean of BC and BA (√30)
- the long side of the large triangle is the geometric mean of the longer segment of the hypotenuse and the whole hypotenuse (x = √66)
- the short side of the large triangle is the geometric mean of the shorter segment of the hypotenuse and the whole hypotenuse (y = √55)
If you were aware of the last of these relationships, you could write down the answer without any "work."
y = √(5(5 +6)) = √55
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The geometric mean is the n-th root of the product of n numbers. When there are 2 numbers, it is the square root of their product.
The following subsets you can be able to create are:
{1}
{2}
{3}
{1,2}
{1,3}
{2,3}
{1,2,3}
Therefore, there are 7 subsets in all. However, we don't have to list all these possible outcomes because we could waste our time doing this but there is a formula, that is 2^n - 1 where n is a number of elements.
In the given, since there are 3 elements inside the set then we use 2^3 - 1 = 8 - 1 = 7.
See...it's easy.