Answer :

You need to subtract the largest number and the smallest, so it would be 12-0, getting an answer of 12.

18, 13, 22, 17, 21, 24}

{17, 19, 22, 26, 17, 14}

{13, 17, 12, 21, 18, 20}

{18, 21, 16, 22, 24, 15}