[tex]A = \Big\{x\in \mathbb{Q}\Big|\, |2x-1| < 99\Big\} \\ \\ |2x-1|<99\,\,\Leftrightarrow\,\,-99<2x-1<99\,\,\Leftrightarrow \,\,-98<2x<100 \,\,\Leftrightarrow \\ \\ \Leftrightarrow -49 < x < 50 \Rightarrow A = (-49,50)\,\cap\, \mathbb{Q} \\ \\ \Rightarrow \text{Cel mai mare element al multimii A este }49,(9)[/tex]