Answer:
The answer is A. Decreased by 4%.
Step-by-step explanation:
Calculations are as shown below:
In the year of 2011:
Modern Electronics working hour's per day = Number of workers x working time per day = 80 x 8 = 640 hours
Number of calculators Modern Electronics made per one working hour ( that is, productivity) = 60,000 / 640 = 93.75 calculators.
In the year of 2012:
Modern Electronics working hour per day = Number of workers x working time per day = 85 x 10 = 850 hours
Number of calculators made per one working hour ( that is, productivity) = 76,500 / 850 = 90.00 calculators.
Comparision of productivity in the year 2012 over the year 2011 = 90/93.75 -1 = -4%
Thus, productivity decrease 4% in the year 2012 in comparison to the year 2011.