Question

(5) For a given set of data, the SAMPLE MIDRANGE = 48. Which of the following comments about the value of the SAMPLE MEDIAN for that data set is MOST reasonable? (A) It must lie within 4.8 units of 48. (B) It must be LESS THAN 48.

(C) NO statement could reasonably be made regarding the possible value of the

SAMPLE MEDIAN. (D) It must be HIGHER THAN 48.

   PLEASE RESPOND TO EITHER QUESTION (6) OR (7), BUT NOT BOTH :

(6) (A) You have a set of 65 data values, whose sample average is 40. Please determine the TOTAL for that data.

(B) You have a set of data values which TOTAL 1575, and AVERAGE 25.

         HOW MANY data values do you actually have ?

(C) WHICH type of sample would you expect to exhibit the MOST bias:

      (i)CONVENIENCE sample (ii) RANDOM sample (iii) STRATIFIED sample

(7) You have a data set having a MEAN value of - 20 and a VARIANCE of 36.

    Using ONLY CHEBYSHEV’S THEOREM:

     (A) AT LEAST WHAT PROPORTION of your data could be expected to lie  

         WITHIN the interval from -38 to - 2 ?

    (B)AT LEAST 75 % of your data MUST lie between which pair of NEGATIVE integers?

Answer 1

5)

For a given set of data, the midrange= 48

then the value of the SAMPLE MEDIAN for that data set:

(B) It must be LESS THAN 48.

6)

n =65

average = 40

total sum = 40*65

=2600

b)

total =1575

average =25

n = total / average

= 1575 / 25

= 63

c)

WHICH type of sample would you expect to exhibit the MOST bias:

CONVENIENCE sample (ANSWER)

Convenience sampling is a sampling technique where subjects are selected because of their convenient accessibility and proximity to the researcher. the researcher did not consider selecting subjects that are representative of the entire population.