Final answer:
To find the number of seals at the San Diego Zoo, use the given ratio and set up a proportion.
Step-by-step explanation:
To find the number of seals at the San Diego Zoo, we can use the given ratio. The ratio of seals to penguins is 5:7. This means that for every 7 penguins, there are 5 seals. If there are 35 penguins, we can calculate the number of seals by setting up a proportion:
5 seals / 7 penguins = x seals / 35 penguins
Cross-multiplying, we get:
7 * x seals = 5 * 35 seals
Simplifying, we find that there are 25 seals at the San Diego Zoo.