Answer:

Step-by-step explanation:
Given

-- City C
--- City K
Required
Determine the 90% confidence interval
This is calculated using:

Calculating 




For a 90% confidence level, the z-score is 1.65. So:

Calculating the standard deviation 

So:


So:


Answer:
Step-by-step explanation:
a. 4x+4y
b. 8a+24b
c. 6x+33y
d. 63a+54b
e. 3ac+bc
f. 2xy+11yz
The sum of the given series can be found by simplification of the number
of terms in the series.
- A is approximately <u>2020.022</u>
Reasons:
The given sequence is presented as follows;
A = 1011 + 337 + 337/2 + 1011/10 + 337/5 + ... + 1/2021
Therefore;
The n + 1 th term of the sequence, 1, 3, 6, 10, 15, ..., 2021 is given as follows;
Therefore, for the last term we have;
2 × 2043231 = n² + 3·n + 2
Which gives;
n² + 3·n + 2 - 2 × 2043231 = n² + 3·n - 4086460 = 0
Which gives, the number of terms, n = 2020


Which gives;


Learn more about the sum of a series here:
brainly.com/question/190295