Running at the same constant rate, 6 identical machines can produce a total of 270 bottles per minute. At this rate, how many bottles could 10 such machines produce in 4 minutes?  Answers
A) 10800  B) 648  C) 1800  D) 2700  E) 180
Let the required number of bottles be x.   More machines, More bottles (Direct Proportion)   More minutes, More bottles (Direct Proportion)   Machines	6: 10 :: 270 : x   Time (in minutes)	1	:	4   6 x 1 x x = 10 x 4 x 270   x =	(10 x 4 x 270)/(6)   x = 1800.   Answer is 1800.
<result>C</result>
Running at the same constant rate, 6 identical machines can produce a total of 270 bottles per minute. At this rate, how many bottles could 10 such machines produce in 4 minutes?