Question

Suppose the age distribution in a city is as follows. Under 18 24% 18–25 16% 26–50 34% 51–65 8% Over 65 18% A researcher is conducting proportionate stratified random sampling with a sample size of 200. Approximately how many people should he sample from each stratum?

Number of people Under 18

enter a number of people 18–25

enter a number of people 26–50

enter a number of people 51–65

enter a number of people Over 65

Answer 1

Solution:

Given:

Age groups	Proportion
Under 18	24%
18–25	16%
26–50	34%
51–65	8%
Over 65	18%

A researcher is conducting proportionate stratified random sampling with a sample size of 200.

Since it is proportionate stratified random sampling, so to get sample from each stratum , we multiply each % by 200.

thus we get:

Age groups	Proportion	Calculations:	Sample Size in each stratum
Under 18	24%	24% of 200=	48
18–25	16%	16% of 200=	32
26–50	34%	34% of 200=	68
51–65	8%	8% of 200=	16
Over 65	18%	18% of 200=	36
			200