If mary cycles at 9 Km/hr, she reaches school late by 5 minutes. If ,however, she cycles at 12/kmhr , she reaches school 3 minutes early .Find the distance of the school from her home.
Here is the link given below for the answer similar to your query :
https://www.meritnation.com/ask-answer/question/missed-the-bus-by-3-minutes-however-if-i-walk-at-5-km/math/3686411
https://www.meritnation.com/ask-answer/question/missed-the-bus-by-3-minutes-however-if-i-walk-at-5-km/math/3686411