中文版：http://www.geogebratube.org/material/show/id/6078 (Download GeoGebra file)

從活動的開始、結束及所用的時間中任何兩個已知量，透過撥動時鐘
的分針及時針，找出剩下的未知量。

輸入活動的開始及結束時間。撥動分針及時針，量度活動用了多少時間；或
輸入活動開始/結束時間，撥動分針和時針至已知的活動所用的時間，找出活動的結束/開始時間

English version:  http://www.geogebratube.org/material/show/id/9312 (Download GeoGebra file)

This applet helps students to find the elapsed time from the given 
starting time and ending time, or to find the starting/ending time 
given the ending/starting time and the time elapsed.

Find the elapsed time from the given starting time and ending time.
Also, we can find the starting/ending time given the ending/starting time and the time elapsed.