Enter the number of teeth in contact and the total number of teeth into the Contact Ratio Calculator. The calculator will evaluate and display the Contact Ratio.

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## Contact Ratio Formula

The following formula is used to calculate the Contact Ratio.

CR = TC / T

- Where CR is the Contact Ratio
- #TC is the number of teeth in contact
- #T is the total number of teeth

To calculate the contact ratio, divide the number of teeth in contact by the total number of teeth.

## How to Calculate Contact Ratio?

The following example problems outline how to calculate Contact Ratio.

Example Problem #1:

- First, determine the number of teeth in contact.
- The number of teeth in contact is given as: 45.

- Next, determine the total number of teeth.
- The total number of teeth is provided as: 100.

- Finally, calculate the Contact Ratio using the equation above:

CR = #TC / #T * 100

The values given above are inserted into the equation below and the solution is calculated:

CR = 45 / 100 * 100 = 45.00 (%)

Example Problem #2:** **

For this problem, the variables required are provided below:

number of teeth in contact = 60

total number of teeth = 750

Test your knowledge using the equation and check your answer with the calculator above.

CR = #TC / #T * 100** = ?**