If 2a + 7b+2c=16 and 2a + 3b +2c= 8, then b = ? (A)-2 (B) O (C) 2 (D) 4 (E) 6
1 answer:
You might be interested in
Answer:
C. Decreases the margin of error and hence increases the precision
Step-by-step explanation:
If we select a sample by Simple Random Sampling in a population of “infinite” size (a population so large that we do not know its size exactly), then the margin of error is given by
where
<em>Z = The Z-score corresponding to the confidence level </em>
<em>S = The estimated standard deviation of the population </em>
<em>n = the size of the sample. </em>
As we can see, since n is in the denominator of the fraction and the numerator is kept constant, the larger the sample size the smaller the margin of error, so the correct choice is:
C. Decreases the margin of error and hence increases the precision