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?
Select.
A) 648	B) 1800	C) 2700	D) 10800	E) 948
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   Therefore, 6 x 1 x x = 10 x 4 x 270   =&gt; x =(10 x 4 x 270) / (6)   =&gt; x = 1800.   Correct answer is 1800.
<result>B</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?