program lai_suat_tiet_kiem;
var
  n, k, m, t: real;
begin
  write('Nhap lai suat tiet kiem (t%/thang): ');
  readln(t);
  t := t / 100;
  
  write('1. Tinh tong so tien (von + lai) sau k thang: ');
  write('Nhap so von ban dau: ');
  readln(n);
  write('Nhap so thang can goi: ');
  readln(k);
  writeln('Tong so tien (von + lai) sau ', k:0:0, ' thang: ', n * power(1 + t, k):0:2);
  
  write('2. Tinh so thang can goi de nhan duoc so tien m: ');
  write('Nhap so tien can nhan: ');
  readln(m);
  write('Nhap so von ban dau: ');
  readln(n);
  k := log10(m / n) / log10(1 + t);
  writeln('So thang can goi: ', k:0:0);
  
  write('3. Tinh so von ban dau can goi: ');
  write('Nhap so tien can nhan: ');
  readln(m);
  write('Nhap so thang can goi: ');
  readln(k);
  n := m / power(1 + t, k);
  writeln('So von ban dau can goi: ', n:0:2);
  
  readln;
end.