If 7 Is Transformed Into 13 And 11 Is Changed To 21 Then What Does 16 Become?

The logic behind the numbers is that we multiplied the number by 2 and then subtracted 1 from the result.

i.e. 7 x 2 – 1 = 14 – 1 = 13

Also 11 x 2 – 1 = 22 – 1 = 21

So to find resultant number for 16 we calculate;

16 x 2 – 1 = 32 – 1 = 31

Answer = 31.