Next Brain Teaser
Jesse wanted into this exclusive club, which has some type of secret password method to enter. So he hid out where he could hear the doorman, thinking that if he listened long enough he would work out the algorithm and gain entry. A lady approached and the doorman said12. The lady responded 6, then entered the club. A gentleman approached, the doorman said 6, and the gentleman responded 3. Hearing enough, Jesse figured he had it worked out. The doorman said 10, Jesse responded 5, and was stopped at the door.
What was the answer and why?