To find the mean number of pets in the line plot, we first need to determine the numbers that each x represents. From the line plot, we can see that the numbers represented by the x's are: 2, 4, 2, 4, 2, 4, 2, 2, 2, 4, 2, 4, 2, 2, 2, 4, 2.
Adding all these numbers together, we get: 2+4+2+4+2+4+2+2+2+4+2+4+2+2+2+4+2 = 48.
There are a total of 17 x's in the line plot, so to find the mean number of pets, we divide the sum by 17: 48 / 17 = 2.82.
Therefore, the mean number of pets is 2.82.