wieviel prozent sind 98 von 121

121   =>    100 %

 98    =>       p  %               p = 98*100/121 = 80,99 %  (gerundet)

$${\frac{{\mathtt{98}}{\mathtt{\,\times\,}}{\mathtt{100}}}{{\mathtt{121}}}} = {\frac{{\mathtt{9\,800}}}{{\mathtt{121}}}} = {\mathtt{80.991\: \!735\: \!537\: \!190\: \!082\: \!6}}$$

oder so:      $${\frac{{\mathtt{121}}}{{\mathtt{100}}}} = {\frac{{\mathtt{98}}}{{\mathtt{p}}}}$$           =>    $${\mathtt{p}} = {\frac{{\mathtt{100}}{\mathtt{\,\times\,}}{\mathtt{98}}}{{\mathtt{121}}}}$$       

$${\mathtt{p}} = {\frac{{\mathtt{100}}{\mathtt{\,\times\,}}{\mathtt{98}}}{{\mathtt{121}}}} \Rightarrow {\mathtt{p}} = {\mathtt{80.991\: \!735\: \!537\: \!190\: \!082\: \!6}}$$

Gruß radix !