The time taken to travel length of track is 150 second
Solution:
Given that children's rollercoaster ride travels along 3300 feet of track at an average rate 15 miles per hour
Distance = 3300 feet
Speed = 15 miles per hour
To find: Time taken to travel this length of the track in seconds
The relation between speed and distance is given as:

----- eqn 1
Let us first convert miles per hour to feet per second
To convert miles to feet multiply by 5,280
1 mile = 5280 feet
To convert hours to seconds, multiply by 3,600
1 hour = 3600 seconds
Converting 15 miles per hour to feet per second

Substituting the values in eqn 1, we get

time = 150 second
Thus the time taken to travel length of track is 150 second