Simple scoring question

[caffrey75]

Think this is a bit of a simple one, so I've posted it in the Simple Stuff section.

Building a dart game and having problems with the scoring field.

When a dart gets thrown into the board, the score associated with the panel it hits gets passed to variable field on the _root called

'dartscore'

However there is also a field called 'roundscore' which displays the points accumulated by each dart and increments itself after every dart is thrown. I thought this would be so simple and my code looked something like this.

[AS] _root.roundscore += _root.dartscore[AS/]

Unfortunately, all that happens is that a long string of numbers appear in 'roundscore' - no Maths is done at all.

I know if I put something like

[AS] _root.roundscore += 4[AS/]

it works! What's the problem here. Have trawled the boards, but can't find anything......