word problems guide 3 chapter 7 page. 125

[agriloka.gmat]

Orange computer is breaking up its conference attendees into groups. Each group must have exactly one person from division A.......

I dont understand how they came up with number " 26"???????????

and 26 division B people (leaving 30-26= 4 left over

I don't get it :((((

[tim]

please read the forum rules and post the entire problem so other students can benefit from the explanation..