Problema Solution
Kindly help me solve this problem:
After 20 minutes into a cross country race, Teck Seng has run 5/8 of the route while Jack has covered only 3/8 of the distance. Teck Seng runs at the same average speed throughout the race and Jack's average speed is
60 m/min slower than Teck Seng's.
a) Find the total distance of the cross country race.
b) If Jack wants to finish the race at the same time as Teck Seng, by how much should he increase his average speed for the remaining part of the race? (Express your answer in m/min)
Thank you in advance.
Answer provided by our tutors
solution/: let teck's's average speed is=x Jack's average speed is = x-60
total distance = d
using speed=dis/time
5d/8=x*20 and 3d/8= 20*(x-60)
solving we get d=4800m
and x=150m/min
B) distance left for jack = 5*4800/8=3000m
and for teck= 1800
time taken by teck for remaining part of track=12min
to complete 3000m in 12 min speed = 250
so increase in speed= 250-90=160