Hi,
Unlike the obsolete English Imperial system (you have to feel for USA students struggling with all those conversions!!) all you have to do is move a decimal point.
So because there are 100 Centimetres (symbol cm) in a Metre (symbol M) then 1.0 cm is 0.01 M. All I did was move the decimal place two places left.
So 1000.0 cm is 10.0 M. To go the other way move the decimal point the other way. Example 0.9M is 900.0cm.
This also works for areas (move 4 places because 100x100 = 10^4) and volumes (move 6 places because 100x100x100 = 10^6)