Question

[(72:a-3x4)x36-19x5]-(124x6-301x2)=195

Answer 1

$[(72:a-12)*36-95]-(744-602)=195$
$[(72:a-12)*36-95]-142=195$
$(72:a-12)*36-95=337$
$(72:a-12)36=432$
$72:a-12=12$
$72:a=24$
$a= \frac{72}{24}$
$a=3$