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.
Answer:
0.1606 = 16.06% probability that the number of births in any given minute is exactly five.
Step-by-step explanation:
In a Poisson distribution, the probability that X represents the number of successes of a random variable is given by the following formula:

In which
x is the number of sucesses
e = 2.71828 is the Euler number
is the mean in the given interval.
In this question:
We only have the mean during an interval, and this is why we use the Poisson distribution.
The mean number of births per minute in a given country in a recent year was about 6.
This means that 
Find the probability that the number of births in any given minute is exactly five.
This is P(X = 5). So

0.1606 = 16.06% probability that the number of births in any given minute is exactly five.
Answer:
I may be wrong but I think 8 is your answer.
Step-by-step explanation:
(-1)^(3/7) x 128^(3/7)
-1 x 128^3/7
128^(3/7) = 8
= 8