two cars left simultaneously from two places p & Q for Q & p respectively.they crossed each other after x hrs.after dat 1 of d car took y hrs & another took z hrs to reach their destinations.which of d following holds true?
x=(y+z)/2
x=2yz/(y+z)
x=SQRT(yz)
x=(y^2+z^2)/(y+z)

• let car A is going from P to Q with speed a and car B is going from Q to P with speed b.
  since they meet after x hr.(and let they meet at point D.)
  so distance travel by car A (PD)=a*x;..........(1)
  and by car B (QD)=b*x;............(2)
  now car A has to cover the distance QD to reach destination
  so distance(QD)=a*y;.........(3)
  similarly by car B (DP)=b*z;......(4)
  so by eq 1 and 4
  a/b=z/x........(5)
  and from 2 and 3
  a/b=x/y........(6)
  from 5 and 6
  x=sqrt(yz);
  
• 12 years agoHelpfull: Yes(29) No(2)
• ans is c but can u mail me questions dear shyamleshd@gmail.com
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• A(p)----------------D--------B(q)
  car a starts from p n car B from q they meet at D
  so,in x hrs dist traveled by A ie AD=a*x
  by BieBD=b*x
  A takes y hrs more so dist ie DB =ay
  n B takes ie DA=bz
  now,AD=DA
  so,ax=bz
  ie a/b=z/x
  n BD=DB
  ie a/b=x/y
  so.x^2=yz
  
• 12 years agoHelpfull: Yes(2) No(0)
• can u please elaborate???
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• @shyamlesh dash::plz mail qns that u r having to my id:g_naresh91@yahoo.com...i have tcs on 27th..plz....
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• x=SQRT(YZ)
  
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