Question

20. Two cyclists, Mike and Josh, simultaneously started toward each other
from two towns d = 24 km apart. Josh rode at Vj = 25 km/h, and Mike
at um = 15 km/h. The moment they start, a fly also starts from Josh
towards Mike and after reaching Mike, immediately returns towards
Josh. The fly continues back and forth motion between the cyclists till
the cyclists meet. Air speed of fly is Uf = 30 km/h and the wind blows
always towards Mike with a constant velocity u = 10 km/h. Find the
total distance s flown by the fly.
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Answer 1

Answer:

18 km

Explanation:

Distance = 24 km

Speed of Mike = 15 km/hr

Speed of Josh = 25 km/hr

Let say after T hrs Mike & Josh Meets

then

15T + 25T = 24

=> 40T = 24

=> T = 3/5 Hrs

=> T = 0.6 hrs

=> T = 36 mins

So fly will fly for 36 mins (0.6 hrs) because after that both cyclist meet

Speed of Fly = 30 km

Distance by Fly = 30 * 0.6 = 18 km