câu 1:

uses crt;
var  n:longint;
begin
clrscr;
readln(n);
if(n mod 3=0)and(n mod 7=0)then writeln('n chia het cho 3 vA 7')else writeln('n khong chia het cho 3 vA 7');
readln;
end.

câu 2:

uses crt;
var  n:longint;
begin
clrscr;
readln(n);
if(n mod 4=0)then writeln(n,' la nam nhuan')else writeln(n,' la nam khong nhuan');
readln;
end.

câu 3:

uses crt;
var  a,b,c,d,e,f:longint;
begin
clrscr;
readln(a,b,c,d,f,e);
a:=a+d;
b:=b+f;
c:=c+e;
repeat
if(c>=60)then begin c:=c-60;b:=b+1;end;
until c<60;
repeat
if(b>=60)then begin b:=b-60;a:=a+1;end;
until b<60;
writeln(a,':',b,':',c);
readln;
end.

câu 4:

uses crt;
var  a,b:longint;
begin
clrscr;
readln(a,b);
if(((a<0)and(b>0))or((a>0)and(b<0)))then writeln('trai dau')else writeln('cung dau');
readln;
end.

câu 5:

uses crt;
var  cd,cr:real;
begin
clrscr;
readln(cd,cr);
if(cd*2*3.14>cr*2*3.14)then writeln('hinh cd lon hin hinh cr')
else if(cd*2*3.14=cr*2*3.14 )then writeln('hinh cd bang hinh cr')
else writeln('hinh cd be hon hinh cr');
readln;
end.