15 meters should be about right. hope this helped
Answer:
1.2 meters.
Step-by-step explanation:
Length of pen = 2x meters
width of pen = x meters
shape of pen is rectangular
we know that area of rectangle is given by length * width
Thus, area of the pen is x*2x = 
It is also given that area of pen is 2.8 square meters.
Equating numerical value of area with area in terms of x, we have

Thus value of x is 1.2 meters.
The ratio of the trout with tags that are caught and the total trout with tags is first calculated.
r = 12 trout / 180 trout = 1/15
Then, we divide the number of trouts caught without tag by the value obtained above.
N = (48 - 12) / (1/15) = 540
Then, we add the number obtained above and 180.
T = 540 + 180 = 720
ANSWER: 720