A can complete 10 rounds of park in the same time as B completes 6 rounds. If circumference of track is 200 m, how much start A can give to B in a race of 1 round?

• Time taken is constant so, A completed 2000m in same time as B completed 1200m.
  i.e we can say when A completed 200m B would be completed 120m.
  (200-120)m =80m start can be given by A to B so that both of them complete 1st round simultaneously.
• 8 years agoHelpfull: Yes(5) No(0)
• ans is 80m
  circumference of track = 200m
  
  A travelled 10 times a 200m tract. So total distance travelled by A = 2000m
  Similarly, for B total distance travelled by B = 1200m
  
  time is constant for A and B
  va/vb=2000/1200
  va/vb=5/3
  
  let x be the start A gives to B
  time taken for A to complete 1 track = time taken by B to complete 200-x track, say x be our required ans.
  ta=200/va=tb
  So distance travelled by B in ta = s*t
  vb*(200/va)
  3/5*(200)=120
  80 + 120
  ie, ................................................
  200
  hence start A gives B is 80
• 9 years agoHelpfull: Yes(1) No(0)
• 
  ans is 120m
  
  
  since track is 200m
  10 rounds means====2000m covered by A
  in the same time as
  6 rounds ====1200m covered by B
  hence time is same
  speed =dis/time
  va/vb=2000/1200
  va/vb=5/3
  va=(5/3)vb
  now for start given by A to complete one round at the same time
  200=(5/3)Dis
  or start to B= 120m
  
  
  
  
• 10 years agoHelpfull: Yes(0) No(1)