mental ability :
if 3+9 =31 , 15+12 = 45 , 18+9= 36 , than 12+25 is equal to
a = 94
b= 14
c=49
d= 53
e = 100
if 3+9 =31 , 15+12 = 45 , 18+9= 36 , then 12+25 is equal to 94
so, the answer is a= 94.