[ChAK_de_fatte]

Originally Posted by rahul20001

if 2 equations x 2 +px+q=0 & x 2 +lx+m=0 have one common root,then how many of following 3 statements can be true?

2)Common root is ( q-m )/(l-p)

2. 1
please post the sol along...
source- powerprep

just equated the two eqns.
it boils down to px + q = lx + m
hence ans.
plz tell me i'm wrong. coz i know i am

[shashankmishra]

Originally Posted by rahul20001

if 2 equations x 2 +px+q=0 & x 2 +lx+m=0 have one common root,then how many of following 3 statements can be true?
1) Common root is (pm-ql)/(q-m)
2)Common root is ( q-m )/(l-p)
3) Square of common root is (pm-ql)/(l-p)

1. 0 2. 1 3. 2 4. 3

please post the sol along...
source- powerprep

Here all the three statements are correct.......... (4) 3

Consider two roots as (-1) and (-2) for one equation and (-2) and (-3) for other equation.....
So we have equations as........

For (-1) and (-2)
(x+1)(x+2) = 0 => x^2 + 3x + 2 = 0 -> Here p = 3 and q = 2

For (-2) and (-3)
(x+2)(x+3) = 0 => x^2 + 5x + 6 = 0 -> Here l = 5 and m = 6

Now substitute the values of p, q, l, m in the terms given you will find that all are correct.

As common root is (-2)..........

[crack_2009]

Let A= {x ; x is a prime number and x<30}The number of different rational numbers whose numerator and denominator belong to A is?

i am getting 91

[uhhh...]

Originally Posted by ChAK_de_fatte

just equated the two eqns.
it boils down to px + q = lx + m
hence ans.
plz tell me i'm wrong. coz i know i am

you are partially correct

to prove the first statement ..divide both equations by x^2.. and solve for 1/x..

for the second one solve both equations for x

for the third solve both equations for x^2..

[rahul20001]

Originally Posted by ChAK_de_fatte

just equated the two eqns.
it boils down to px + q = lx + m
hence ans.
plz tell me i'm wrong. coz i know i am

the oa for this is 3...i got this one, wanted to know for others...thanks anyway..

[uhhh...]

Originally Posted by crack_2009

Let A= {x ; x is a prime number and x<30}The number of different rational numbers whose numerator and denominator belong to A is?

i am getting 91

90.. donno where i am losing 1 more such arrangement

[rahul20001]

Originally Posted by crack_2009

Let A= {x ; x is a prime number and x<30}The number of different rational numbers whose numerator and denominator belong to A is?

i am getting 91

hey which is the 91st value...90 values are straight...

[simrat_sandy]

sorry i had made a mess of your post so had to deleted your question,
please see the sequence below, hope it is clear

Originally Posted by brajesh.pandey

P(0)-----------------------------------------------------180(Q)
a--->................................................. ..........................<--b
a travelled for 72/2 =36................(a,b)............................. ....

P(0)---------------------------72(m1 a,b)-----------------180(Q)
.............................................<--b,a-->........................
.................................................a travels for 108/2 =54


P(0 b)-----------------------------108-----------------------180(Q a)
b--->................................................. ..........................<--a
.................................................. .(b,a)a travels for 72/2 =36

[simrat_sandy]

people please look into these questions also

Originally Posted by simrat_sandy

hello all, please provide detailed solutions for these, thanks

x set out at 12:00 noon to walk from borivali to bandra, and a friend y started at 2 pm on the same day to walk from bandra to borivali by the same road. they met on the road at 5 min past four o'clock, and both of them reach their destination at exactly the same time. at what time did they both reach their destination?
5 pm
6 pm
7 pm
8 pm

anand,brijesh, chandan run a race. anand finishes 20m ahead of brijesh and 15m ahead of chandan.chandan in a race, finishes 10 m ahead of brijesh. each participant travels the entire distance at a constant speed then what is the length of the race?
25m
30m
35m
40m

two boats x and y start from A at the same time towards B at the same constant speed of 15 km/hr in still water. boat x goes to B
whereas boat y goes till C which is equidistant from A and B and returns to A. if the time taken by x is 1.5 times as that of y, what is the speed of the current
10 km/hr
7.5km/hr
5km/hr
data insufficient

[jaidev_iyer]

Originally Posted by jaidev_iyer

In the last summer vacation, Divishth was given an assignment of writing down numbers from 100 to 1000. Despite all his brilliance and intelligence, he gets confused between the digits 6 and 9, and ends up interchanging them.

Q1: How namy numbers did he write correctly in his assignment ?
1. 343
2. 353
3. 448
4. 512
5. None of these

Q2: As a punishment, his teacher asks him to write down the difference btwn the actual number and the number he wrote, for all his incorrectly written numbers. However, he repeats the same mistake while writing the difference btwn the two numbers. How many times did he write the difference incorrectly?
1. 352
2. 176
3. 36
4. 18
5. None of these

Official Answers:
1.None of these(449)
2.18