Tim and elan are 90km away from one another.they are started to move each other simultaneously.tim at 10km/hr and elan at a speed of 5km/hr/.if every hour doubles their speeds.what is the distance that tim will pass untill he meets elan.
A.45km
N.80km
C.30km
D.60km

• Ans option d)60km
  
  1: For first hour Tim,Elan speeds are 10kph,5kph dist.covered=15kph*1h=15km (speed adds when walking towards each other).
  2: For second hour speeds 20kph,10kph dist. covered =30kph*1h=30km.
  3:For third hour lap speeds will be 40kph,20kph so the meeting will occur in this laponly.
  dist. remaining(90-45=45km)
  Time taken = 45km/60kph = 3/4h
  Total time for the meeting =2 3/4 hr
  Now to calculate dist. covered by tim we succesively multiply speeds of tim with lap time like:
  1.1hr*10kph=10km
  2.1hr*20kph=20km
  3.3/4hr*40kph=30km
  SO total dist.tim will pass untill meets elan =10+20+30=60km
• 10 years agoHelpfull: Yes(22) No(0)
• 60km .....jst read d ques carfuly ..u l gt it
  
• 10 years agoHelpfull: Yes(2) No(6)
• D.60km
  For 1st one hour tim pass 10km simultaneously elan pass 5km after that their speed get double i.e after 1 hr tim pass 20km and elan 10 km respectively.and after 1hr tim pass 40km and total of 70km and elan pass 20 km and total of 30km so in the travel of his 60km he met elan.
• 10 years agoHelpfull: Yes(1) No(1)
• actually distance doubles for each hour for the first time 10,5...second time it doubles to 20,10..third 40,20...if again we done for fourth time means 80,40...80+40=120 which exceeds from original 90km so we need to stop upto 3rd doubling which is 406+20=60...so finnally answer distance is 60
  
• 10 years agoHelpfull: Yes(0) No(0)
• we know average speed=5+10=15
  time=dist/av speed=90/15=6
  dist by tim=10*6=60
• 9 years agoHelpfull: Yes(0) No(0)
• As speed of Tim will always be twice as the speed of Elan, so Tim will always cover twice distance as compared to Elan.
  So just break 90 into 3 equal parts i.e., 30 each,
  Now Tim will cover 2*30=60km
  while Elan will cover 1*30=30km
• 6 years agoHelpfull: Yes(0) No(0)