Bài 1

uses crt;
var x,y:integer;
procedure rutgon(var x,y:integer);
var a,b,x1,y1:integer;
begin
x1:=x;
y1:=y;
a:=x;
b:=y;
while a<>b do
begin
if a>b then a:=a-b;
if a<b then b:=b-a;
end;
if a=1 then writeln('Phan so da duoc toi gian') else
begin
x1:=x div a;
y1:=y div a;
if y1<>1 then writeln(x,'/',y,'=',x1,'/',y1) else writeln(x,'/',y,'=',x1);
end;
end;
begin
clrscr;
write('Nhap tu: ');readln(x);
write('Nhap mau: ');readln(y);
rutgon(x,y);
readln
end.
Bài 2

uses crt;

var a,b,i,s,dem:integer;

begin

clrscr;

for i:=1 to 100 do begin

for a:=2 to i-1 do if i mod a=0 then b:=b+1;

if b=0 then begin

dem:=dem+1;

s:=s+i;

end;

b:=0;

end;

writeln('Co ', dem, ' so nguyen to');

writeln('Tong cac so nguyen to la: ',s);

readln

end.