Step 1. Given: The puffin has 12 small fish in its bill and the weight of those fish is 148 grams.
Required: Find the average weight of one fish.
Step 2. To find the average we need to divide the sum of the weight of all of the fish by the number of fish:

Step 3. Solving the division the result is:

The average weight is 12.33 grams.
Answer: 12.33 grams