If you do not have a conversion table, you can convert between systems as long as you know one key equation: 2.54 centimeters equals 1 inch. From there you can build a chain of fractions.
Example: How many meters are in 8 feet?
feet → inches → centimeters → meters
Cancel out the feet, inches, and centimeters by flipping the fractions, then multiply and divide to get your answer.