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sweet
May 1st, 2003, 05:37 AM
ok guys, here's one for the smart one!

there are 2 trains(say train A and train B) coming towards each other on the same track both at 30km/hr.
At present the difference between them is 60km and one bird starts flying form train A to train B and again to train A and then to train B and it repeats this cycle till the 2 trains collide..

now you have to tell how much distance the poor bird covered before the accident if the speed of the bird is 60km/hr ??

cheers!

satyeshwar
May 1st, 2003, 09:19 AM
60 Kms

mbamal
May 1st, 2003, 09:30 AM
Hi Soma,
anyone who has prepared for IITJEE can come up with a solution to this question in seconds...its 60 kms.......the time taken by trains to collide is 1 hour....

relative distance(60 km)/Relative velocity between trains(30 +30 = 60)

..and speed of bird is 60km/hr so the ans is 60 km.

or if someones wanna complicate it...then the time interval between two successive collisions wll be a part of infinite GP with common ratio 1/3 and first term 2/3...if u sum them then total time comes to be 1 hours...

navingulia
May 1st, 2003, 10:37 AM
bhai bamal aur satyeshwar donu e fail ho gaye. the bird will take 1hr/60km if trains were stationary with 60km gap but the trains are closing in so the bird will have to fly less than 60km ie less than an hour.
yo e tai catch thaa

navingulia
May 1st, 2003, 10:40 AM
answer is 40 min, 40km
just consider the bird and the other train, they have to cover 60km togather with a speed of 60+30=90kmph. they will take 60/90 hrs=40min and the bird will travel 40km in those 40min.

OHO YO BAAT TAI MANNAI DEKHI E NAHIN, PAKSHI NAI ULTA BHI UDNA SAI? BHAI FER TAI 60MIN 60KM AI LAAGAINGE.

BHAI THUM BHI KATI E MAAROGE PAKSHI NAI UDA UDA KAI. HA HA HA

mbamal
May 1st, 2003, 07:54 PM
bhai navin,

ek aur baat se...the bird has to make infinite trips...between the two trains...to wah to ud ud ke pelha ee mar jaageey...

akdabas
May 1st, 2003, 09:32 PM
Bird to abhee bhee fly kar raha hei. Jab ruk jaga to us se puchoonga ke bhai kitne km. total udda.

Ha...Ha...Ha.........

mbamal
May 1st, 2003, 10:29 PM
ha ha ha....dabas bhai...puzzle to aadmi ne banayi...isee tessi bechare bird kee kar deee

rsdalal
May 1st, 2003, 11:34 PM
Theoritically Bird will travell more than 59.9999999999 KM but less than 60 KM.
So I support Bagh's answer 6oKM

akdabas
May 2nd, 2003, 05:18 AM
Very funny.

Mandeep brother, baat khoob kahi aapne. Maja aa gaya. Thodi der tak to bas hansta hee raha.
Ha..Ha..Ha..............


Mandeep Bamal (May 01, 2003 12:59 p.m.):
ha ha ha....dabas bhai...puzzle to aadmi ne banayi...isee tessi bechare bird kee kar deee

akdabas
May 2nd, 2003, 05:20 AM
Ranvir Bhai,

Apne bhee lagta hei poora dimag laga diya answer karne mein. Looks like your answer is very accurate. :)

Ha..Ha..Ha.......



Ranvir Singh Dalal (May 01, 2003 02:04 p.m.):
Theoritically Bird will travell more than 59.9999999999 KM but less than 60 KM.
So I support Bagh's answer 6oKM

rsdalal
May 2nd, 2003, 05:51 PM
Ha Ha Ha ....

Ashok Kumar Dabas (May 01, 2003 07:50 p.m.):
Ranvir Bhai,

Apne bhee lagta hei poora dimag laga diya answer karne mein. Looks like your answer is very accurate. :)

Ha..Ha..Ha.......



Ranvir Singh Dalal (May 01, 2003 02:04 p.m.):
Theoritically Bird will travell more than 59.9999999999 KM but less than 60 KM.
So I support Bagh's answer 6oKM

amar0974
May 3rd, 2003, 02:12 PM
Bhai Ashok kyon Puzzle ho re so Us Paksi ka ek 'Meter' la do na Aapa bera pata ja ga jitney bhey kilometer kaada ga.
Bhai Rukan ke baat dekho ge ta bera na pher jinda ra ak na ra
Hahahaaaaaaaaaaa

Ashok Kumar Dabas (May 01, 2003 12:02 p.m.):
Bird to abhee bhee fly kar raha hei. Jab ruk jaga to us se puchoonga ke bhai kitne km. total udda.

Ha...Ha...Ha.........

mbamal
May 3rd, 2003, 05:12 PM
Bazaad bhaisahab ka solution sabse fit hai....log khamkhah main hee apna dimag laga rahe hain...bus ek meter la do...magar bazaad bhai ya bhi to indian pakshi se...iska meter to ghana tez chalega...aur jitne km dodegee..uske double dikhavega meter..

akdabas
May 4th, 2003, 07:54 AM
Mandeep & Amardeep Bhai,

Lage se yo meter bhee kite foreign te import karna parega.....

Ha..Ha...Ha..Ha..Ha..Ha......................


Mandeep Bamal (May 03, 2003 07:42 a.m.):
Bazaad bhaisahab ka solution sabse fit hai....log khamkhah main hee apna dimag laga rahe hain...bus ek meter la do...magar bazaad bhai ya bhi to indian pakshi se...iska meter to ghana tez chalega...aur jitne km dodegee..uske double dikhavega meter..

rkumar
May 5th, 2003, 06:00 AM
Distance (a vector) travelled by the bird is 30 KM as it has to fly between two trains only..Two trains are going to collide exatclt at 30 km distance ..mid way..and the bird has to be on either of those two trains at the time of collision...I assume the trains are point trains as Soma ji has not given the length of trains...To be more precise the distance travelled=30km+/- train length..

Rajendra