hi im going to be using a pressure sensor soon, an omron D8M-A1 trying to work out the maths but hit a wall could someone tell me how to work out this figure out please

sensors output is...... 15mv to 1247mv. over a pressure range 0 millibar to 49millibar.

i need to know what value when @ 12 milibar,

i thought i had it but then noticed 0millibar was 15mv which threw me out

thank you