To get this answer you need to keep counting 24 seconds until it gets to exactly a minute, no seconds over or under, so 24x5=120 which is 2 minutes so it will be 2 minute. In other words to solve this you need to find a common factor 1 minute equals 60sec so 60x2=120 which is 2 min. So in 2 minutes the gears will be aligned again.
