Tds

[Shubham Jain]

[Abhilash Chandra]

9:12

On Sat, Feb 15, 2014 at 4:10 PM, Shubham Jain <jain.sh...@gmail.com> wrote:

--
 
---
You received this message because you are subscribed to the Google Groups "Sui Generis" group.
To unsubscribe from this group and stop receiving emails from it, send an email to suii_generis...@googlegroups.com.
For more options, visit https://groups.google.com/groups/opt_out.

[Shubham Jain]

I no th ans but want to know the approach...which approach used by u abhilash?

[Shubham Jain]

A and B starts a race in a circular track of 1800m length at a speed of 40m/m and 50m/m respectively. After one round B reverse its direction. So how many minutes will they take to meet?

[Abhilash Chandra]

apparently answer is root(16*9).....its a standard formula ..

if u wanna know hw it works dn read below.

-----------------------------------------------------------------

X                                               Y

a goes for T mins                       b goes for T min

after meeting a takes 16       b takes 9

so-----------------------

distance travelled by a in second half= a*16(let a is his speed )

so 16*a=bT( let b is speed and T is meeting time as mentioned above)-------(1)

similarly, 

9*b=aT------------(2)

use 1 and 2;

a/b=3/4

now meeting time T= total distance/(a+b)=> 16a+9b/(a+b)=> 12mins

On Sat, Feb 15, 2014 at 10:58 PM, Shubham Jain <jain.sh...@gmail.com> wrote:

A and B starts a race in a circular track of 1800m length at a speed of 40m/m and 50m/m respectively. After one round B reverse its direction. So how many minutes will they take to meet?

--

[Abhilash Chandra]

q2........4 mins after b completes one round.

---------------------------------------------------------------

A takes 1800/40=45 min

B takes 1800/50=36 min.

when B completes 1 round ,position of A is 40*36=1440 , remaining =360,

since B reverses so time= 360/(40+50)=4 min