Previous answers do not disappear entirely - they can be scrolled back to.

There are two reasons for this:

• It provides a sense of how much they've achieved
• For the next question, they may use an earlier question as a starting point (ie if the question is 8×7, and they recently did 8×6 they may count 8 from their (always correct) answer to 8×6. They'll be feeling good about themselves because not only was it quick, they got one over on The Man. We applaud their initiative because maths is the art of making a hard problem easy. But what else happened? Well, they reinforced their memory of 8 ×6.