[tex]\underline{\underline{Notez:}}\\
a-\ \textgreater \ numarul ~de ~copii~absenti~;\\
p-\ \textgreater \ numarul~de~copii~prezenti~;\\\\
\boxed{a= \frac{1}{7}*p}~~~=\ \textgreater \ ~~ \boxed{p=7*a}\\\\
a+2 = \frac{3}{13} * ( p- 2) \\\\
13a +2*13= 3( p -2)\\\\
13a +26 = 3p - 6 ~~~(~inlocuim ~pe ~p~ca~\boxed{p=7a}~)\\\\
13a +26 = 3*7a -6 \\\\
13a +26 = 21 a -6 \\\\
26 +6 = 21a-13a\\\\
32 = 8a\\\\
a= \frac{32}{8}\\\\
\boxed{\boxed{\bold{\underline{a=4}}}} \\\\
p= 7*4 \\\\
\boxed{\boxed{\bold{\underline{p=28}}}} [/tex]