Donkey Kong Jr. Math

There is a record for \"Calculate 10\". But where or what is this mode?

I just checked how it is in my version (pal) and I also don't know where to play calculate 10.. What version is that on the page? perhaps it's different in us or jap? However, the scores that we have in pal version are: 00 + 00 000 - 000 0000 + 0000 0000 - 0000 0 x 0 000000 + 000000 000000 - 000000 000 x 00 00 : 0 and the scores you get are highscores, best wins.