From the following comparative statements of the years 2010 and 2011:

(a) Find out whether the year 2011 showed an overall better performance or otherwise:

(b) Possible causes of difference:

 

2010

2011

Wages incurred

2,80,000

5,10,000

Units produced

16,000

25,000

Average number of workers

225

400

(Assume production of only one quality and same machinery conditions in both years).