It's all I can do

So Shelle over at Blok-Thoughts is doing the "Don't you hate it when" contest for a second month. I have never gotten any votes, but it's still good fun. So here goes ...

I'm in school. Working hard to get my assignments in on time, but it's not working out so well. After a few mediocre assignment grades, I thought my marker might be penalizing me for late submissions. But in hindsight, I don't think he is.

Why?

Because on my most recent assignment, which I submitted on time, my marker docked me three of the five available marks on one question because I didn't specify per unit profit of $36. But the question asked for total profit, not per unit profit. And I showed the calculation as the number of units sold multiplied by this: ($180 - $144), where $180 is the selling price per unit and $144 is the cost per unit. So out of curiosity, what does $180 - $144 equal? And why did I lose three marks?

I hate it when that happens. Don't you?

Now, go and visit Shelle. Read. Vote. Play. Have fun! I'm going to go beat my head against the wall until things start making sense to me. It's all I can do.