To find out how many miles the whale swims in 16 days, we can set up a proportion between the number of days and the number of miles.
The proportion can be set up as follows:
(days the whale swims) / (miles the whale swims) = (days) / (miles)
In this case, since we know that the whale swims 200 miles in 5 days, we can substitute those values into the proportion:
5 / 200 = 16 / x
Cross-multiplying, we get:
5x = 200 * 16
Simplifying the right side of the equation, we have:
5x = 3200
To solve for x, we divide both sides by 5:
x = 3200 / 5
x = 640
Therefore, the equation that could be used to find how many miles the whale swims in 16 days is:
y = 640
Note: The equation "y = 200 × 16" is incorrect because it does not take into account the relation between days and miles swum. The other equations provided are also incorrect or unnecessary.