Six and a half what?
You need to define your desired units of measurement for the six and a half.
For example:
6.5 centimeters = 65 millimeters
6.5 inches = 165.1 millimeters
Six decimeters is greater than sixty millimeters. One decimeter is equal to one hundred millimeters so six decimeters would equal six hundred millimeters.
5.6mm is 'five and six-tenths millimeters'. OR five point six millimeters
One centimeter is 10 millimeters, therefore one and a half centimeters is 15 millimeters.
5 millimeters is half of a centimetre. It is approximately equal to 0.2 inches.
The answer is 500