Option A
is one way to determine the factors of
by grouping
<em><u>Solution:</u></em>
Factoring by grouping means that you will group terms with common factors before factoring
<em><u>Given expression is:</u></em>
Group the first two terms together and then the last two terms together.
We can see that is common in first two terms
And 3 is common in last two terms
Factor them out
Thus option A is correct
Answer:
Sample mean from population A has probably more accurate estimate of its population mean than the sample mean from population B.
Step-by-step explanation:
To yield a more accurate estimate of the population mean, margin of error should be minimized.
margin of error (ME) of the mean can be calculated using the formula
ME= where
for a given confidence level, and the same standard deviation, as the sample size increases, margin of error decreases.
Thus, random sample of 50 people from population A, has smaller margin of error than the sample of 20 people from population B.
Therefore, sample mean from population A has probably more accurate estimate of its population mean than the sample mean from population B.