To find out how many miles the whale swims in 16 days, we first need to determine the average number of miles it swims per day. Since the whale swims 200 miles in 5 days, we can calculate the daily distance:
\[ \text{Daily distance} = \frac{200 \text{ miles}}{5 \text{ days}} = 40 \text{ miles per day} \]
Now, to find out how many miles it swims in 16 days, we can multiply the daily distance by 16:
\[ y = 40 \times 16 \]
Therefore, the correct equation to find how many miles the whale swims in 16 days is:
y = 40 × 16