If it takes a tub 3 minutes to drain 6/7 of its content, how much more time will it take for the tub to be empty?
Pick one
A) 30 seconds	B) 1 minute, 12 seconds	C) 1 minute, 50 seconds	D) 2 minutes, 14 seconds	E) 4 minutes, 12 seconds
If 6/7 of tub's content is drained 1/7 th of tub still needs to be drained.   If it takes 3 minutes to drain 6/7 th of tub it takes 3*(7/6) minutes to drain the entire tub and 3*(7/6)*(1/7) min to drain 1/7 th of the tub which is 6/5 minutes or 0.5 minutes or 30 seconds   So answer is 30 seconds
<result>A</result>
If it takes a tub 3 minutes to drain 6/7 of its content, how much more time will it take for the tub to be empty?