3
multiply by 4
12
add 12
24
divide by 2
12
subtract 6
6
number 6 : 6(4) = 24... + 12 = 36...36/2 = 18.....- 6 = 12
number 8 : 8(4) = 32....+ 12 = 44...44/2 = 22....- 6 = 16
number 12: 12(4) = 48....+ 12 = 60...60/2 = 30....-6 = 24
well...by following these steps, it appears the original number doubles as a result.