Brain Game: A Four-Spot Drop
By BY

By changing one letter at a time to form different English words, and leaving all other letters in their original positions, convert SIXTH into TENTH in the fewest steps possible. Good luck!
S I X T H _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ T E N T H
Here is a 7-step SOLUTION.
A 7-STEP SOLUTION:
SIXTH > SIXTY > SILTY > SILTS > TILTS > TINTS > TENTS > TENTH
Did you come up with a different sequence of words? Feel free to share it by commenting below.