Machine P and Machine Q are each used to manufacture 770 sprockets. It takes Machine P 10 hours longer to produce 770 sprockets than Machine Q. Machine Q produces 10% more sprockets per hour than Machine A. How many sprockets per hour does Machine A produce?  Pick one:	A) 3	B) 5	C) 7	D) 9	E) 11
P makes x sprockets per hour.   Then Q makes 1.1x sprockets per hour.   770/x = 770/1.1x + 10   1.1(770) = 770 + 11x   11x = 77   x = 7   The answer is 7.
<result>C</result>
Machine P and Machine Q are each used to manufacture 770 sprockets. It takes Machine P 10 hours longer to produce 770 sprockets than Machine Q. Machine Q produces 10% more sprockets per hour than Machine A. How many sprockets per hour does Machine A produce?