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:
<em>b. 5 + 17i</em>
Step-by-step explanation:
Answer:
-1/3
Step-by-step explanation:
1/3 is 0.33333... and then you just put a negative sign in front of it.
Answer:
Convenience sampling.
Step-by-step explanation:
To gather information on customer satisfaction, a researcher goes into each store and interviews six randomly selected customers at each store. This sampling technique is called convenience sampling.
Convenience sampling can be defined as a sampling method which involves the researcher selecting or collecting data that is easily available or choosing the individuals who are easiest to reach in a population. It is a type of non-probability method of sampling where the first or easiest available data source is being used by the researcher without other requirements.
In this scenario, to gather information on customer satisfaction, the researcher went to the store most likely situated in a shopping mall to collect data from six (6) customers in each stores.
<em>Some of the advantages of convenience sampling are low cost, data are collected quickly, lesser rules etc. </em>
<span>Simplifying
4x2 + 8xy + 4y2
Reorder the terms:
8xy + 4x2 + 4y2
Factor out the Greatest Common Factor (GCF), '4'.
4(2xy + x2 + y2)
Factor a trinomial.
4((x + y)(x + y))
Final result:
4(x + y)(x + y)</span>
