We have the function d, representing the distance from the ground of a person riding on a Ferris wheel:
If we consider the position of the person at t = 0, which is:
This position, for t = 0, will be the same position as when the argument of the sine function is equal to 2π, which is equivalent to one cycle of the wheel. Then, we can find the value of t:
Then, the wheel will repeat its position after t = 60 seconds.
Answer: 60 seconds.