Tough and Tricky questions: Percents.
Over the course of a year, a certain microbrewery increased its beer output by 20 percent. At the same time, it decreased its total working hours by 30 percent. By what percent did this factory increase its output per hour? Answers:	A) 171.4	B) 171.5	C) 171.6	D) 171.7	E) None of the above
Lets assume the initial production was 100 litres of beer for 100 hr.   With the 20% increase the total amount of beer production will be 120 litres and with 30 % decrease in total hours will be reduced to 70 hr.   100hr ----&gt; 100 lts   1hr -----&gt; 1 lts   70hr -----&gt; 120 lts   1hr -----&gt; 1.714 lts   Total Increase in production for 1 hr = 171.4%   171.4nswer 171.4
<result>A</result>
Tough and Tricky questions: Percents.
Over the course of a year, a certain microbrewery increased its beer output by 20 percent. At the same time, it decreased its total working hours by 30 percent. By what percent did this factory increase its output per hour?