To find out how many miles the whale swims in 16 days, we first need to determine its swimming rate in miles per day.
The whale swims 200 miles in 5 days. Therefore, the rate of swimming can be calculated as follows:
\[ \text{Rate} = \frac{200 \text{ miles}}{5 \text{ days}} = 40 \text{ miles per day} \]
Now, to find out how far it swims in 16 days, we can multiply this rate by 16 days:
\[ \text{Distance} = 40 \text{ miles/day} \times 16 \text{ days} = 640 \text{ miles} \]
Thus, the correct equation that could be used to find how many miles it swims in 16 days is:
\[ y = 40 \times 16 \]
So the answer is:
y = 40 × 16 (Response: y = 40×16)