A mile is made up of 1609.34 meters. Any time you are measuring distance, this will be a good conversion to memorize. Any time you have a specific number of miles and you need to convert them into meters, you can use the number 1609.34 to find the answer with only the use of a calculator (or you can potentially do it in your head or on paper!).
So for an example, if you have 3 miles and the equation asks for an answer in meters, you can simply multiply 3 by 1609.34 to get the answer. That answer would be 4828.02 meters in 3 miles. This might be important to memorize for someone working in transportation or on the road ways.