GMAT Data Sufficiency Discussions

MBA GMAT
1621
Q2:
If 2 different representatives are to be selected at random from a group of 10 employees and if p is the probability that both representatives selected will be women, is p > 1/2 ?
(1) More than half of the 10 employees are women.
(2) The probability that both representatives selected will be men is less than 1/10


again the question is incomplete.. I have filled per my understanding..

the answer must be option E

possible combo are;
M-M
W-M/M-W
W-W

eqn 2 does not help as it provides the probab for both men.. option B and option D are out of question now..

eqn 1 does not help on its own either.. even if half are more than women, lets say 6. the probab would be (6/10)x(5/9) = 1/3.. doesnt help answer the question.. so eqn A is also out of question..

comnbining the 2 does not help either.. u can test and be sure..

so the answer must be option E

lemme know the OA.. 😉
1622
kshankareswaran Says
hey guys......need help.........i have started with my DS prep...but i face a lot of problems to find whether the quest can b solved with any 1 option or both or its insufficient.pls help..what can i do to improve

What kind of question is this buddy?:shocked:

anyways... there is only 1 mantra to improve:

Practice !!! Solve 20 sums a day from OG and in 7 days OG will be over !!!

Post the problems you are not able to solve... Puys will help you surely !!!

Good Luck !!!
1623
Q2:
If 2 different representatives are to be selected at random from a group of 10 employees and if p is the probability that both representatives selected will be women, is p > 1/2 ?
(1) More than of the 10 employees are women.
(2) The probability that both representatives selected will be men is less than 1/10


The answer is E.
2.Let there will be M men.
so m(m-1)m=2,3
so total number of woman could be-8,7
if we calculate by 8,answer will be>.5
and from 7 answer will be<.5>
1624
E should be correct:
nutty...I am adding one more thing in navy color just to help others understand:
again the question is incomplete.. I have filled per my understanding..

the answer must be option E

possible combo are;
M-M
W-M/M-W
W-W

eqn 2 does not help as it provides the probab for both men.. option B and option D are out of question now..

eqn 1 does not help on its own either.. even if half are more than women, lets say 6. the probab would be (6/10)x(5/9) = 1/3.. which is less than 1/2

Now lets say there are 8 women.
probability will be 28/45 which is greater than 1/2.

doesnt help answer the question.. so eqn A is also out of question..

comnbining the 2 does not help either.. u can test and be sure..

so the answer must be option E

lemme know the OA.. ;)
1625
The answer is E.
2.Let there will be M men.
so m(m-1)m=2,3
so total number of woman could be-8,7
if we calculate by 8,answer will be>.5
and from 7 answer will be<.5>

Gutsy, sorry buddy...but could you explain as what is logic to say:

M(M-1) = 9??
1626
Gutsy, sorry buddy...but could you explain as what is logic to say:

M(M-1) = 9??


yaar i supposed m man and then-
select two man from 10=>m(m-1)/10*9m(m-1)
1627
yaar i supposed m man and then-
select two man from 10=>m(m-1)/10*9m(m-1)
Guys with Guts...
It should be m(m-1)/5*9 and not 10*9
1628
Guys with Guts...
It should be m(m-1)/5*9 and not 10*9

why u make it half?
1629
guy with guts Says
why u make it half?

10C2 buddy...


When selecting people in a group, using Permutations is a very bad idea

Consider A,B,C,D,E and F

A,B is the same as B,A. The order doesn't matter only the people in the group does. Therefore Combinations!!
1630
10C2 buddy...
When selecting people in a group, using Permutations is a very bad idea
Consider A,B,C,D,E and F
A,B is the same as B,A. The order doesn't matter only the people in the group does. Therefore Combinations!!

yaar I have taken mC2/10C2 and both 2 cancel each other.I have taken combinations only.
1631
guy with guts Says
yaar I have taken mC2/10C2 and both 2 cancel each other.I have taken combinations only.


Ohh...

My mistake
1632
Q2:
If 2 different representatives are to be selected at random from a group of 10 employees and if p is the probability that both representatives selected will be women, is p > 1/2 ?
(1) More than of the 10 employees are women.
(2) The probability that both representatives selected will be men is less than 1/10



I got with E.

Neither of the choices give the number of men women so difficult to calc the probablity.
1633
What is the value of x + 7?
(1) x + 3= 14
(2) (x + 2)2 = 169


One more:

Is x=y?
(1) x - y = 6
(2) x + y = 0
1634

Ans for the below one is

What is the value of x + 7?
(1) x + 3= 14
(2) (x + 2)2 = 169


Statement 1:
==========
x+3 = 14 or -(x+3) = 14

x = -17 or x = 11.

Statement 2:
==========
x+2 = +/- 13

x = 11 or x = -15.

so combining both the statements gives x = 11

Please post the OA

1635

Ans for the below one :

Is x=y?
(1) x - y = 6
(2) x + y = 0


statement 1 :
==========
x -y = 6 .Can have multiple values.

Statement 2:
===========
x = -y which gives x = y provided x and y is not equal to zero.So statement 2 is not suff.

But combining both, we get x = 3 and y = -3 which will give us the result.

Please post the OA

1636
Ans for the below one is

What is the value of x + 7?
(1) x + 3= 14
(2) (x + 2)2 = 169


Statement 1:
==========
x+3 = 14 or -(x+3) = 14

x = -17 or x = 11.

Statement 2:
==========
x+2 = +/- 13

x = 11 or x = -15.

so combining both the statements gives x = 11

Please post the OA



Answer says B)...i dont't know how, thats why i posted this here...

But i'm sure C shd be the answer...
1637
Ans for the below one :

Is x=y?
(1) x - y = 6
(2) x + y = 0


statement 1 :
==========
x -y = 6 .Can have multiple values.

Statement 2:
===========
x = -y which gives x = |y provided x and y is not equal to zero.So statement 2 is not suff.

But combining both, we get x = 3 and y = -3 which will give us the result.

Please post the OA


Well, answer says B...but IMO, must be D...

look at as what exactly is being asked...

IS X| = |Y ???

and equation is x-y = 6...

there is a direct answer to this, which says "NO"...its not possible that X| = Y...
1638
What is the value of x + 7?
(1) x + 3= 14
(2) (x + 2)2 = 169

IMo C x =11 if combined
One more:
Is x=y?
(1) x - y = 6
(2) x + y = 0


IMo D

From 1) the ans is no
from 2) the ans is yes
1639
Well, answer says B...but IMO, must be D...

look at as what exactly is being asked...

IS X = |Y ???

and equation is x-y = 6...

there is a direct answer to this, which says "NO"...its not possible that X| = Y...



What is the source of these questions?
1640
Well, answer says B...but IMO, must be D...

look at as what exactly is being asked...

IS X = |Y ???

and equation is x-y = 6...

there is a direct answer to this, which says "NO"...its not possible that X| = Y...


Hi Amsey,
Only by seeing x-y = 6 you cannot conclude because x = 3 and y = -3 can yield u 6 and also serve as yes for the main q.So only by seeing this statement we cannot conclude anyting.