DECLARE
 lv_promo_txt CHAR(1) := 'B';
 lv_total_num NUMBER(6,2) := 100;
 lv_disc_num NUMBER(5,2);
BEGIN
  lv_disc_num := CASE lv_promo_txt 
   WHEN 'A' THEN lv_total_num * .05
   WHEN 'B' THEN lv_total_num * .10
   WHEN 'C' THEN lv_total_num * .15
   ELSE lv_total_num * .02
 END;
 DBMS_OUTPUT.PUT_LINE(lv_disc_num);
END;