Let's solve the problem step-by-step:
1. Identify the number of koi and non-koi fish:
- Number of koi fish = 7
- Number of non-koi fish = 3
2. Calculate the total number of fish in the pond:
- Total number of fish = Number of koi fish + Number of non-koi fish
- Total number of fish = 7 + 3 = 10
3. Determine the ratio of the total number of fish to the number of fish that are not koi:
- The total number of fish is 10.
- The number of non-koi fish is 3.
4. Express the ratio in simplest form:
- The ratio of total fish to non-koi fish is 10 to 3.
Therefore, the correct answer is:
(D) 10:3
