Question

500m race a gives b a head start 125 m and wins by 10s .if a gives b a head start of 150 mthe race emds in a dead head . what will be the time taken (in seconds ) by a to complete the race?

Answer 1

Ravi beats ramesh by 5 sec or 100 mtr....means ramesh cover 100mtr in 5 sec....by this we can get ramesh speed in 20m/sec
20.............in 1 sec
500........in 500/20=25 sec(Ramesh's time)

so ravi take 20 sec to cover 500 mtr......by this we can get that ravis speed is 25m/sec

now assume x be the distance from staring line where we need to put the winning post.
According to question ravi’s speed will be 25*2=50m/sec & ramesh’s speed will be 20*1.5=30 m/sec

now assume x be the distance from staring line where we need to put the winning post.

they will take same time to reach the wining post.
As ravi gives Ramesh a 200 m ahead start so he has to accede x meter and Ramesh has to accede (x-200) meter
Hence we may write,
x/50=(x-200)/30
x=500 meter