# Thread: Need Help on this Quiz

1. ## Need Help on this Quiz

There are two bicycle riders travelling towards each other, each travelling at 10Km/hr and the distance between them is 60km. There is also a butterfly that is flying back and forth at 20km/hr between the two riders until it is finally crushed when both riders meet at the mid-point.
Question:
• what is the time duration of the butterflies second last lag (i.e. flying from rider 1 to rider 2)?
• what is the time duration of the butterflies last lag (i.e. flying back to rider 1 where it meets its DEATH)
• Is there a simple formula of working this out?
Appreciate the help

2. Originally Posted by taval79
There are two bicycle riders travelling towards each other, each travelling at 10Km/hr and the distance between them is 60km. There is also a butterfly that is flying back and forth at 20km/hr between the two riders until it is finally crushed when both riders meet at the mid-point.

Question:
• what is the time duration of the butterflies second last lag (i.e. flying from rider 1 to rider 2)?
• what is the time duration of the butterflies last lag (i.e. flying back to rider 1 where it meets its DEATH)
• Is there a simple formula of working this out?
Appreciate the help
Is there a last leg?

RonL