How do you calculate speed from ratios and input or output speed?

To calculate speed from ratiOS and input or output speed, you can use the formula: ( \text{Output Speed} = \text{Input Speed} \times \text{Ratio} ). If you have the input speed and the ratio of output to input, simply multiply the input speed by this ratio to find the output speed. Conversely, if you have the output speed and need to find the input speed, you can rearrange the formula: ( \text{Input Speed} = \frac{\text{Output Speed}}{\text{Ratio}} ).