Question 615151
If a tire rotates at 400 revolutions per minute when the car is travelling 72km/h, what is the circumference of the tire?
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Use quantitative analysis method to solve:
let c=circumference
..
72km/hr*min/400 rev*hr/60min*rev/c
hr, min, rev, cancel out
=72000m/c*60*400
=3m/c
circumference=3m