Honestly, Mo should have been writing down the numbers. He'd thrown down his quill at R2... something and then just hoped against hope that they wouldn't be asked to tally up the numbers.

And then they were asked to tally up the numbers. It was good some of his classmates had written everything down, but Mo couldn't shake the feeling they were wrong. Call it his Ravenclaw instinct, but since the guy up at the front of the room had only a passing acquaintance with generally accepted history, he might also only be passingly acquainted with the concept of addition.

Maths wasn't really a Wizarding subject, anyway. So maybe it was a riddle. Mo scrunched up his shoulders a bit and offered, "I think it's... the number of hairs on your head times the number of stars in the sky plus the grains of sand on the beaches of Mars. Plus R2-D-thingy plus Obi Kobi-thingy plus... 2i." And Mo gave West an apologetic look for that.