Question

Ilya and Anya each can run at a speed of 8.30 mph and walk at a speed of 3.30 mph . They set off together on a route of length 5.00 miles . Anya walks half of the distance and runs the other half, while Ilya walks half of the time and runs the other half.
How long does it take Anya to cover the distance of 5.00 miles ?
How long does it take Ilya to cover the distance?
Find Ilya's average speed.

Answer 1

For Anya:v 1 = 3.3 mph,   v 2 = 8.3 mph5 : 2 = 2.5 mi ( half of the distance )
t1= d/v1 = 2.5 mi/ 3.3 mph = 0.7576 ht2 = d/v2 = 2.5 mi/8.3 mph = 0.3 hIn total: 0.7576 + 0.3 = 1.0576 hFor Ilya: 8.3 t / 2 + 3.3 t / 2 = 5   / * 28.3 t + 3.3 t = 1011.6 t = 10t = 10 : 11.6t = 0.86 hHe covers the distance for 0.86 h.His average speed:v = 5/0.86 = 5.81 mph.