Battery Arithmetic

[steve30]

Often when I buy cells (aka "batteries"), the quantity tends to be an expression, rather than a value on its own. Today I bought 4+2 cells. Also available were some packs of 10+1 cells. I've also seen packs of 4+4 in shops, and on a website the other week I saw a pack of 16+16.

Its a good job I know how to add