Answer:
Step-by-step explanation:
We want to determine a 90% confidence interval for the true population mean textbook weight.
Number of sample, n = 22
Mean, u = 64 ounces
Standard deviation, s = 5.1 ounces
For a confidence level of 90%, the corresponding z value is 1.645. This is determined from the normal distribution table.
We will apply the formula
Confidence interval
= mean ± z ×standard deviation/√n
It becomes
64 ± 1.645 × 5.1/√22
= 64 ± 1.645 × 1.087
= 64 ± 1.788
The lower end of the confidence interval is 64 - 1.788 = 62.21 ounces
The upper end of the confidence interval is 64 + 1.788 = 65.79 ounces
Therefore, with 90% confidence interval, the true population mean textbook weight is between 62.21 ounces and 65.79 ounces
Answer:
Step-by-step explanation:
<u>Step 1</u>:-
Given problem is [(x + 1)(x - 1)]^2
by using formula in side square bracket is
![[x^{2} -1]^{2}](https://tex.z-dn.net/?f=%5Bx%5E%7B2%7D%20-1%5D%5E%7B2%7D)
<u>Step 2</u>:- again we will use formula
^{2} = (x^{2}) ^{2} -2 x^{2} (1)+1^{2}](https://tex.z-dn.net/?f=%5Btex%5D%28x%5E2-1%29%5E%7B2%7D%20%3D%20%28x%5E%7B2%7D%29%20%5E%7B2%7D%20-2%20x%5E%7B2%7D%20%20%281%29%2B1%5E%7B2%7D)
[/tex]
on simplification we get
<u>Final answer:-</u>
<u />
Answer:
x=3
Step-by-step explanation:
4x-x=9
3x=9
x=3
