Answer:
a) 
With:


b) 

c) 

d) 


Step-by-step explanation:
For this case we know the following propoertis for the random variable X

We select a sample size of n = 81
Part a
Since the sample size is large enough we can use the central limit distribution and the distribution for the sampel mean on this case would be:

With:


Part b
We want this probability:

We can use the z score formula given by:

And if we find the z score for 89 we got:


Part c

We can use the z score formula given by:

And if we find the z score for 75.65 we got:


Part d
We want this probability:

We find the z scores:



I believe it would be 4 lil man
Answer:
, x ≠ -1/4
Explanation:We are given that:
f (x) = 4x + 1
g(x) = x² - 5
We want to find the value of (g/f)(x). This means that we will simply divide g(x) by f(x) as follows:

Now, we should note that any function is undefined if its denominator is equal to zero.
This means that for our current function:
4x + 1 cannot be equal to zero
4x + 1 = 0
4x = -1
x = -1/4
This means that the value of x cannot be -1/4, otherwise, our function would be undefined.
Based on the above, the last option is the correct one.
Hope this helps :)
The value of the constant k when the value of x and y is 7 and 3 respectively in the equation xy=k is 21.
<h3>What is an equation?</h3>
An equation is formed when two equal expressions are equated together with the help of an equal sign '='.
The value of the constant k when the value of x and y is 7 and 3 respectively in the equation xy=k can be written as,

Hence, the value of the constant k when the value of x and y is 7 and 3 respectively in the equation xy=k is 21.
Learn more about Equation:
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