Question

deimpartit 416
impartitor
cat 13
rest 13

Answer 1

$416 \div x = 13 \: r13$
$416 = 13x + 13$
$13 x = 416 - 13$
$13x = 403$
$x = 31$

Answer 2

$416 \div a = 13 \: rest \: 13 \\ \\ a = (416 - 13) \div 13 \\ \\ a = 403 \div 13 \\ \\ a = 31$