First find the number of minutes in 2 hours: 2 hours * 60 minutes/hour = <<2*60=120>>120 minutes
Then add 10 minutes to that amount to find the total number of minutes Walter spent at the zoo: 120 minutes + 10 minutes = <<120+10=130>>130 minutes
Let s be the amount of time he spends looking at the seals and p be the amount of time he spends looking at the penguins. From the problem, we know that s + p + 13 = 130 and p = 8s.
Substituting the second equation into the first, we get s + 8s + 13 = 130
Combining like terms, we get 9s + 13 = 130
Subtracting 8 from both sides, we get 9s = 117
Dividing both sides by 9, we get s = 13
#### 13