Given:
Sample mean = 65.4
Standard deviation = 1.2
Sample size = 45
Confidence level = 99%
To find:
The confidence interval.
Solution:
The formula for confidence interval is

where,
is sample mean, z* is confidence value, s is standard deviation and n is sample size.
Confidence value or z-value at 99% = 2.58
Putting the given in the above formula, we get




Therefore, the correct option is D.
Answer as an improper fraction = 16/5
Answer as a mixed number = 3 & 1/5
Answer in decimal form = 3.2
All of those values represent the same thing, but written in a different way.
=============================================================
Explanation:
I'm assuming HM stands for Harmonic Mean in this case.
If so, then we apply the reciprocal operation to each value to get 1/2 and 1/8 (from 2 and 8 respectively).
Add up those fractions:
1/2 + 1/8 = 4/8 + 1/8 = 5/8
Now we'll divide n = 2 over that result. The n = 2 refers to the number of items in the original set.
n divide over (5/8) = 2*(8/5) = 16/5 which is the answer as an improper fraction
-----------
To convert to a mixed number, we can do the following:
16/5 = (15+1)/5
16/5 = 15/5 + 1/5
16/5 = 3 + 1/5
16/5 = 3 & 1/5
Or if you need the answer in decimal form, then using a calculator would get you 16/5 = 3.2
Answer:
as a fraction it could be 3/5
Step-by-step explanation:
but as a decimal it would be 0.6
Answer:
literally google graphing calculator and type 3x
Answer:
n+1=x-1
Step-by-step explanation:
as n goes up, x decreases by 1 each time