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:



Answer:
Step-by-step explanation:
<u>Given:</u>
- AB = 192 cm
- AC : CB = 1 : 3
- CD = BC/12
- The distance between midpoints of AD and CB = x
<u>Find the length of AC and CB:</u>
- AC + CB = AB
- AC + 3AC = 192
- 4AC = 192
- AC = 192/4
- AC = 48 cm
<u>Find CB:</u>
<u>Find the length of CD:</u>
- CD = BC/12 = 144/12 = 12 cm
<u>Find the length of AD:</u>
- AD = AC - CD = 48 - 12 = 36 cm
<u>Find the midpoint of AD:</u>
<u>Find the midpoint of CB:</u>
- m(CB) = AC + 1/2CB = 48 + 144/2 = 48 + 82 = 130 cm
<u>Find the distance between the midpoints:</u>
Answer: Rounded to the nearest tenth is 5
4.96894409 is the exact answer
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Answer:
yes
Step-by-step explanation: