Akey difference between calculating the sample mean and the population mean is that: a. we use and n instead of µ and n. b. we divide the sum of the observations by n - 1 instead of n. c. the sample observations are ranked and the middle value is selected as the population mean. d. there are no differences.

In statistic, the arithmetic mean is one of the ideal measures of central tendency. For a given set of observations, the computation means can be calculated by adding all the comments and dividing the value obtained by the number of views. There are two types of mean, the, i.e., the sample mean and population mean, which is often used in statistics and probability. What the example says is mainly used to estimate the population mean when population means is not known as they have the same expected value.

d. bc = 12 and ef = 16

step-by-step explanation:

we are given that δabc : δdef such that .

also, it is given that

so, from the options, we need that .

a.

b.

c.  

d.

as, we can see that only option d gives the same ratio as i.e. .

hence, the possible lengths are bc = 12 and ef = 16.