Răspuns:
a=5.
Explicație pas cu pas:
(a+aa)-(0,a+0,aa)=58,95,
[tex]a+10a+a-(\dfrac{a}{10} +\dfrac{aa}{100})=12a - (\dfrac{a}{10}+\dfrac{10a+a}{100})= 12a-(\dfrac{10a}{100}+ \dfrac{11a}{100} )=12a-\dfrac{21a}{100}=\dfrac{1200a}{100} - \dfrac{21a}{100}=\dfrac{(1200-21)a}{100}=\dfrac{1179a}{100}\\deci,~\dfrac{1179a}{100}=\dfrac{5895}{100}\\[/tex]
⇒1179·a=5895, ⇒ a=5895:1179, ⇒ a=5.