@Messy_19 said:A train takes 's' seconds to cross a boy standing on platform P. Find the lenght of train.I. It can cross P which is 200m long in t secs.II. Its speed is 60 KmphDS
Either of two would be sufficient...
@Messy_19 said:A train takes 's' seconds to cross a boy standing on platform P. Find the lenght of train.I. It can cross P which is 200m long in t secs.II. Its speed is 60 KmphDS
@19rsb said:can not b answered even by using both.......
bhai tell d aproach ....for my betterment.....as I m getting CBD
We have to consider 's' and 'P' as values given over here. So answers in terms of s and p are acceptable..
@19rsb said:can not b answered even by using both.......
@jain4444 said:@Messy_19 explain how ? I am getting CBD
@19rsb said:bhai tell d aproach...for my betterment
Length of train = (speed)*s
From 1: Speed= (200+l)/t .. Hence we can calculate "l"
From 2: Speed = 60kmph ..Hence we can calculate "l"
Obviously..these variables have some value..and not just variables..
@jain4444 said:@Messy_19 explain how ? I am getting CBD
sir variable s is given in the question. so even if it comes in the ans. it shud be accepted. other variables are based on the individual statements.
@Brooklyn said:appraoch ??
since its a 4 digit no. and less than 3600
it has to be 31^2
and AB and CD are perfect squares
Now we know that to find the square root we will use the division method ...the-taking-2-at-a-time one(AB then CD) (i don't exactly know the name 😛 )
now from eqn1, ab has to be 4^2 or 5^2 (3^2 doesnt give a 2 digit no)
now check for both.. we will get only 41 to be giving a non-zero-digit ans.
@Messy_19 said:We have to consider 's' and 'P' as values given over here. So answers in terms of s and p are acceptable..
@ScareCrow28 said:Length of train = (speed)*sFrom 1: Speed= (200+l)/t .. Hence we can calculate "l"From 2: Speed = 60kmph ..Hence we can calculate "l"Obviously..these variables have some value..and not just variables..
oh tere ki .....eee toh faster k action mein ......spin daal diya aap logon ne......
If p, q and r are in arithmetic progression, the line px + qy + r = 0 necessarily intersects which of the following circles?
OPTIONS
1) x^2 + y^2 + 4x – 4y + 7 = 0
2) x^2 + y^2 – 6x + 6y + 13 = 0
3) x^2 + y^2 – 4x – 6y + 9 = 0
4) x^2 + y^2 + 8x = 0
5) Cannot be determined
aaj toh
subhah-2 code fat gaya
OPTIONS
1) x^2 + y^2 + 4x – 4y + 7 = 0
2) x^2 + y^2 – 6x + 6y + 13 = 0
3) x^2 + y^2 – 4x – 6y + 9 = 0
4) x^2 + y^2 + 8x = 0
5) Cannot be determined
aaj toh
subhah-2 code fat gaya @19rsb said:oh tere ki .....eee toh faster k action mein ......spin daal diya aap logon ne......
"dusra" is a better word 
A and Bcan doa apiece of work in 40 and 50days if they worka t an alternative days with A beginning in how many days the work will be finished
@sujamait said:If p, q and r are in arithmetic progression, the line px + qy + r = 0 necessarily intersects which of the following circles?OPTIONS1) x^2 + y^2 + 4x – 4y + 7 = 0 2) x^2 + y^2 – 6x + 6y + 13 = 0 3) x^2 + y^2 – 4x – 6y + 9 = 0 4) x^2 + y^2 + 8x = 0 5) Cannot be determinedaaj toh subhah-2 code fat gaya
option 4?
@jain4444 said:"dusra" is a better word A and Bcan doa apiece of work in 40 and 50days if they worka t an alternative days with A beginning in how many days the work will be finished
44 (2/5)?
@sujamait said:If p, q and r are in arithmetic progression, the line px + qy + r = 0 necessarily intersects which of the following circles?OPTIONS1) x^2 + y^2 + 4x – 4y + 7 = 0 2) x^2 + y^2 – 6x + 6y + 13 = 0 3) x^2 + y^2 – 4x – 6y + 9 = 0 4) x^2 + y^2 + 8x = 0 5) Cannot be determinedaaj toh subhah-2 code fat gaya
4 option
Option 4 lag raha hai..
Center -4,0; radius 4
@sujamait said:If p, q and r are in arithmetic progression, the line px + qy + r = 0 necessarily intersects which of the following circles?OPTIONS1) x^2 + y^2 + 4x – 4y + 7 = 0 2) x^2 + y^2 – 6x + 6y + 13 = 0 3) x^2 + y^2 – 4x – 6y + 9 = 0 4) x^2 + y^2 + 8x = 0 5) Cannot be determinedaaj toh subhah-2 code fat gaya
@jain4444 said:"dusra" is a better word A and Bcan doa apiece of work in 40 and 50days if they worka t an alternative days with A beginning in how many days the work will be finished
Edit: 45th day?
@Messy_19 said:Option 4 lag raha hai..Center -4,0; radius 4
@maddy2807 said:4 option
@ScareCrow28 said:option 4?
p, q and r are in A.P.
∴ 2q = p + r
px + qy + r = 0
∴ 2px + 2qy + 2r = 0
∴ 2px + (p + r)y + 2r = 0
∴ p(2x + y) + r(y + 2) = 0
This equation is satisfied when 2x + y = 0 and y + 2 = 0, whatever the values of p and r may be.
Solving 2x + y = 0 and y + 2 = 0, we get x = 1 and y = −2
Thus the line px + qy + r = 0 necessarily passes through (1, − 2), whatever the values of p, q and r may be.
The slope of the line will be –p/q, which is indeterminate.
So we can only say that the line necessarily intersects any circle that passes through (1, −2).
We substitute x = 1 and y = −2 in the options to find the correct solution.
We find that only the circle in option 2 passes through (1, −2).
Hence, option 2.
200 units total work.
A can do 5/day; B can do 4/day
2 days mai 9 units,
44 days mai 198.
A's turn, so 2/5 days to complete 200 units
44 2/5
@jain4444 said:"dusra" is a better word A and Bcan doa apiece of work in 40 and 50days if they worka t an alternative days with A beginning in how many days the work will be finished
@sujamait said:If p, q and r are in arithmetic progression, the line px + qy + r = 0 necessarily intersects which of the following circles?OPTIONS1) x^2 + y^2 + 4x – 4y + 7 = 0 2) x^2 + y^2 – 6x + 6y + 13 = 0 3) x^2 + y^2 – 4x – 6y + 9 = 0 4) x^2 + y^2 + 8x = 0 5) Cannot be determinedaaj toh subhah-2 code fat gaya
2?
@sujamait said:p, q and r are in A.P.∴ 2q = p + rpx + qy + r = 0∴ 2px + 2qy + 2r = 0∴ 2px + (p + r)y + 2r = 0∴ p(2x + y) + r(y + 2) = 0This equation is satisfied when 2x + y = 0 and y + 2 = 0, whatever the values of p and r may be.Solving 2x + y = 0 and y + 2 = 0, we get x = 1 and y = −2Thus the line px + qy + r = 0 necessarily passes through (1, − 2), whatever the values of p, q and r may be.The slope of the line will be –p/q, which is indeterminate.So we can only say that the line necessarily intersects any circle that passes through (1, −2).We substitute x = 1 and y = −2 in the options to find the correct solution.We find that only the circle in option 2 passes through (1, −2).Hence, option 2.
Sirjee... It's not necessary that 2x+y be = 0 ..If p=0 then (2x+y) need not be 0
Then we only get y=-2
If we put y=-2 in option (4) ..We get real values of "x"
Likewise..if we put..r=0..then we only get (2x+y)=0..From there also we get real values
So, why not option 4?? 
I guess the question should have given" p, q, and r are non-zero numbers in AP" ??
@ScareCrow28 said:Sirjee... It's not necessary that 2x+y be = 0 ..If p=0 then (2x+y) need not be 0Then we only get y=-2If we put y=-2 in option (4) ..We get real values of "x"Likewise..if we put..r=0..then we only get (2x+y)=0..From there also we get real valuesSo, why not option 4??
yar,yeh bhi ho sakta hai but not necessarily...
jo OA hai usmein woh pakka hee cut karega..aapke case mein it may be, may not be.
jo OA hai usmein woh pakka hee cut karega..aapke case mein it may be, may not be.