Answer to Question #30362 in Economics for awanish singh

Question

Two research workers classified some people in income groups on the basis of sampling studies. Their results are as follow:
Investigators
Income groups
Total
Poor
Middle
Rich
A
160
30
10
200
B
140
120
40
300
Total
300
150
50
500
Show that the sampling technique of atleast one research worker is defective.