Răspuns:
Program P1;
var cla, clb, clc, s, total: Integer;
begin
readln(cla);
clb:= cla * 3; //aflam nr. de elevi din cl. 5-b
s:= cla + clb;
clc:= s - 4; //aflam nr de elevi din cl. 5-c
total:= cla + clb + clc;
writeln( 'In excursie va pleca ' ,total, ' elevi ');
end.
