Answer:

Step-by-step explanation:
<u>Confidence Interval</u>
When the population standard deviation
is known, the formula for a confidence interval for a population mean
is:

Where n is the sample size and z is the corresponding z-value from the standard normal distribution for the selected confidence level. The value of z for a 95% confidence interval is z=1.96. The rest of the values are

Calculating the confidence interval


Or, equivalently

Given:
Normal price of a tv = $200
Coupon = 25% off
To find:
The money saved by Katherine.
Solution:
Katherine buys a tv with a normal price of $200 and she has a 25% off coupon. It means, the money saved by Katherine is 25% of normal price of tv, i.e., $200.




Therefore, the money saved by Katherine is $50.
Answer:
24ab-8ac
Step-by-step explanation:
Assuming you want to simplify it.
Original equation: 8a(3b+6c-7c)
Apply 8a to each variable in the paranthesis: (8a)(3b)+(8a)(6c)+(8a)(-7c)
After multiplication: 24ab+48ac-56ac
Combine like terms: 24ab-8ac
The geometry sequence has the equation
.
The 5 represents the first number of the sequence and the 3 represents the common ratio.
a(5) = 
answer: 405