SOLUTION: Please help A bike wheel has a diameter of 65cm and the bike is travelling at 25 km/h. Determine the time it takes , in seconds for the wheel to make 5 revolutions. round to the

Algebra ->  Circles -> SOLUTION: Please help A bike wheel has a diameter of 65cm and the bike is travelling at 25 km/h. Determine the time it takes , in seconds for the wheel to make 5 revolutions. round to the      Log On


   

Question 973707: Please help
A bike wheel has a diameter of 65cm and the bike is travelling at 25 km/h. Determine the time it takes , in seconds for the wheel to make 5 revolutions. round to the nearest 2 decimal places.
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
One revolution consumes one circumference of distance.
2pi%2865%2F2%29=65pi as cm.

Put that in kilometers.
65pi%28cm%29%281%2F100%29%28m%2Fcm%29%281%2F1000%29%28km%2Fm%29
%2865pi%29%2F%28100000%29, KILOMETERS, the circumference of the wheel.

Five Revolutions makes 5%2865pi%29%2F100000 kilometers.
325pi%2F100000km

Speed of travel is 25 km/h; how much time?
highlight%28%28325pi%2F100000%29%281%2F25%29%2A60%2A60%2ASECONDS%29.
Just compute this number of seconds.