Google’s Employment Applicant’s Hourglass Problem

Ref: March 2012 issue of Wired magazine.

It seems the Google job interview process requires a problem to be solved. I’ll take this hourglass problem, “Using only a four-minute hourglass and a seven-minute hourglass, measure exactly nine minutes.”

Solution Principle: Use one hourglass to measure out a smaller amount of time on the other hourglass. Repeat until you have the correct time periods stored in each hour glass such that when you add their times together by turning the second one up when the first finishes you get the correct total time of nine minutes. Continue reading “Google’s Employment Applicant’s Hourglass Problem”