Question

There is an operation so that when you put in a 2 you get a 6 when you put in a 4 you get a 12 what do you get when you put in a 7

Answer 1

The operation is a number multiplied by 3, so when you "put in" a 7, the answer will then be 21.

Answer 2

Each time the second number is the first multiplied by three. 2*3 is 6 and 4*3 is 12. Likewise, 7*3 is 21 so the answer would be 21 :)