I think we presume a great deal in suggesting that a simple flat array of characters and operators is somehow less understandable than a nicely typeset equation (especially when you've never written one before!).
One advantage would be that you could try invalid syntax and operations (i.e. x/0) and see the errors that result in real time as opposed to an hour or a day later after the teacher marks up your test. Then you're more likely to stick with it until you get it right, which in turn means the answer is more likely to stick with you.