Solving a Classroom Problem

I often find situations when students came late to class, and I did not know when to conclude class.  That was because students’ watches or mobile phones did not keep time properly, and I usually forgot mine. So I once asked students who came late to collect their watches and cellular phones to see whether they kept time correctly, a possible reason for their tardy coming. In fact, none of them showed the right time. Some are 15 minutes late, some 10 minutes, others turned out to be fast 5, 10, 11 minutes. To solve the problem - to know the correct time, I asked the students to find the average of how much their time piece  is fast or late. When intending to finish the class, I asked what the time was. Students’ response were always different

Once we called a watch repairer to repair the broken watches and Hp for economic reason. It is cheaper to fix them in big number than in small one. 

by: Drs. M.Nababan, M.Hum