Respuesta :
Let b=boxes  SO 25=b(2.50)+3.98  So she would be able to buy 8.4 total boxes.
let's b is the number of boxes of cereal Lindsey can buy
  (3.98 + 2.50)b = 25
      6.48 b    = 25
          b     = 3.85
so Lindsey can buy 3.85 boxes of cereal
  (3.98 + 2.50)b = 25
      6.48 b    = 25
          b     = 3.85
so Lindsey can buy 3.85 boxes of cereal