A gear ratio is calculated by dividing the number of teeth on the driven gear by the number on the drive gear. A drive gear with 12 teeth turning a driven gear with 36 teeth produces a ratio of:

a.3:1
b.1:3
c.4:1
d.2:1

Explanation

Dividing 36 driven teeth by 12 drive teeth gives a 3:1 reduction, meaning the drive gear turns three times for each output revolution. This multiplies torque while reducing speed. Understanding ratios is essential for diagnosing driveline gearing and speedometer calibration.

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