You counted 3(80) as 3(8) = 24, instead of 3(1) = 3. Any number (except 0) raised to the 0 power equals 1. The last term of our expression is therefore equal to 3, not 24.
We put this answer in only to have a plausible-looking alternative, so you would have actually to work out the answer. You really shouldn’t be reading 80 as 8 at this stage of the game.
