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 20 such machines produce in 4 minutes?	Choose the correct choice from the following
A) 648 B) 1800 C) 2700 D) 10800 E) 3600

Rationale: "solution let the required number of bottles be x . more machines , more bottles ( direct proportion ) more minutes , more bottles ( direct proportion ) â ˆ ´ 6 ã — 1 ã — x = 20 ã — 4 ã — 270 â ‡ ” x = 20 x 4 x 270 / 6 = 3600 . answer e"
Answer: E