sadhanapriya
Bunuel, need more clarity on statement 2.
Number of surveyors : Number of people surveyed per surveyor
x : 0
2x : 1
2x : 2
4 : 10
1 : 20
The frequency table above shows the number of surveyors together with the corresponding number of surveyed people per surveyor. What is the value of x?(1) The average (arithmetic mean) of the number of people surveyed per surveyor is 3
The total number of surveyed people equals x*0 + 2x*1 + 2x*2 + 4*10 + 1*20 = 6x + 60.
The total number of surveyors equals x + 2x + 2x + 4 + 1 = 5x + 5.
Therefore, based on this statement, the average is (6x + 60)/(5x + 5) = 3. Solving this equation gives x = 5. Sufficient.
(2) Exactly half of the surveyors have surveyed at most one person
This implies that the number of surveyors who surveyed 0 or 1 person was half of the total number of surveyors. The number of surveyors who surveyed 0 or 1 person is x + 2x = 3x. Hence, it is given that 3x = 1/2*(5x + 5). Solving this equation also results in x = 5, which is sufficient.
Answer: D.