Running at the 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?
In one minute 6 identical machines produce 270 bottles.
That means, in one minute one machine produces 270/6 = 45 bottles.
That means, in four minute one machine produces 45*4 = 180 bottles.
That means, in four minute 10 identical machines produce 180*10 =1800 bottles.
So, the answer is (B).
GMAT : Model Questions Index