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?

Since 6 identical machines in 1 minute can produce a total of 270 bottles.
∴ 1 identical machines in 1 minute can produce a total of 270 / 6 bottles.
∴ 10 identical machines in 1 minute can produce a total of 270 x 10 / 6 bottles.
∴ 10 identical machines in 4 minute can produce a total of 270 x 10 x 4 / 6 bottles.
∴ 10 identical machines in 4 minute can produce a total of 45 x 10 x 4 bottles.
∴ 10 identical machines in 4 minute can produce a total of 1800 bottles.