If you take a moment and solve each equation (find the value
of the letter in each one), it'll jump out at you.
Here, let me do it for you. Why should you tire yourself.
5x = 20 . . . . . x = 4
4b = 7 . . . . . . b = 7/4
8w = 32 . . . . . w = 4
12y = 48 . . . . . y = 4
The second equation is not like the others.
It's the only one where the letter is not equal to 4 .