# A 36-tooth gear turns three times. It is connected to a 12-tooth gear. How many times does the 12-tooth gear turn?

##### 1 Answer

Jul 29, 2018

#### Explanation:

The gear ratio of meshed gears is in the inverse ratio of their teeth.

So the gear ratio of the 12-tooth gear to the 36-tooth gear is

To understand this, if the 12-tooth gear turns once, 12 teeth pass the point where the gears mesh.

Therefore 12 teeth on the 36-tooth gear also pass that point.

But 12 teeth on the 36-tooth gear is

So for every turn of the 12-tooth gear the large gear rotates

If the large gear turns 3 times the small gear turns