Question

My watch is 5 minutes slow, but i think it is 3 minutes fast. I arrive 'on time' according to my calculations to catch the 1:15 pm train What is the real time when I arrive at the station?

Answer 1

1:15 pm + 5 minutes =1:20 PM  You add 5 minutes because your watch is slow then subtract 3 minutes because you thought the watch was 3 minutes fast. real time is 1:17 PM
 1:20 pm  - 3 minutes = 1:17 PM