QBASIC Program to print the series 10, 8, 6, 4, 2

Using FOR...NEXT

CLS
FOR i = 10 TO 1 STEP -2
      PRINT i;

NEXT i
END

Using WHILE...WEND

CLS
i = 10
WHILE i >= 1
      PRINT i;
      i = i - 2
WEND
END

Using DO ... LOOP

CLS
i = 10
DO WHILE i >= 1
      PRINT i;
      i = i - 2
LOOP
END