GMAT Data Sufficiency Discussions

MBA GMAT
2021
Yes...Ans for this one has to be C ..

St 1 : tells us nothing...not suff...

St 2 : t-r = t+s
Hence, either r = -s OR 2t = r-s ...not suff ...

Combined : t+s is +ve and t-r is +ve ...

Hene, r=-s only ...

Ans C


Thanks Bhavin. This does solve the problem, but I have a question here.

2t=r-s : This is not possible if we look at the figure given. For r-s to be equal to 2t, t will have to lie between r and s. Does this then mean that we need to ignore the relative positions given in the figure.

Please respond in general terms, related to all questions that have figures.
2022
Thanks Bhavin. This does solve the problem, but I have a question here.

2t=r-s : This is not possible if we look at the figure given. For r-s to be equal to 2t, t will have to lie between r and s. Does this then mean that we need to ignore the relative positions given in the figure.

Please respond in general terms, related to all questions that have figures.


Hey Ankit ...sorry for not being elaborative earlier ...In a hurry did not give a detailed explanation ...

The above situation does hold ground for the given figure ...

Figure only tells us that r
2023

Hi!

Help needed with these 2 Ques:-

1. Are x and y both +ve?
a) 2x-2y = 1
b) x/y > 1

2. A construction company was paid a total of 5 Lakh for a project. the project's only costs were labour
and materials. Was the profit greater than 1.5 Lakh?
a) Total cost was 3 times the cost for materials.
b) Profit was greater than the cost for labour.

\m/

2024

1. (a) Insufficient as x,y can be + as well as -
(b) Insufficient as x,y can be both + and can be both -ve but x > y.
a and b together: all the -ve values of x/y > 1 are eliminated by (a). So, I think "C" is the anwer..

2. (a) Insufficient
(b) Insufficient
a and b together: cost of material = x, cost of labour = 2x
Profit = cost of labout + K. this can or cannot be more than 1.5 lakh.
So, i'll go with E

Hi!

Help needed with these 2 Ques:-

1. Are x and y both +ve?
a) 2x-2y = 1
b) x/y > 1

2. A construction company was paid a total of 5 Lakh for a project. the project's only costs were labour
and materials. Was the profit greater than 1.5 Lakh?
a) Total cost was 3 times the cost for materials.
b) Profit was greater than the cost for labour.

\m/
2025
Hi!

1. Are x and y both +ve?
a) 2x-2y = 1
b) x/y > 1


\m/




statement 1:
============
x - y = 0.5.Nt suff x = -0.5 y = -1 x = 0 y = -0.5.Nt suff

statement 2:
============
x > y . x= 2.5 y = 2

I will go with option C
2026
Hi!

2. A construction company was paid a total of 5 Lakh for a project. the project's only costs were labour
and materials. Was the profit greater than 1.5 Lakh?
a) Total cost was 3 times the cost for materials.
b) Profit was greater than the cost for labour.

\m/



statement 1:
============
c = L + M c = 3M. Nt suff

statement 2:
============
P = L + x


Combining also we can't get a unique solution.
I will go with option E
2027
Hi!

Help needed with these 2 Ques:-

1. Are x and y both +ve?
a) 2x-2y = 1
b) x/y > 1

2. A construction company was paid a total of 5 Lakh for a project. the project's only costs were labour
and materials. Was the profit greater than 1.5 Lakh?
a) Total cost was 3 times the cost for materials.
b) Profit was greater than the cost for labour.

\m/


Q1.

Statement 1-
x=0, y= -0.5
x=1, y=0.5
x= -1, y= -1.5

so x and y both can be -ve or +ve, Statement 1 is insufficient.

Statement 2-
x/y> 1, all improper fractions are there with +ve as well as -ve values.
Statement 2 is also insufficient.

Taking both Statements 1 and 2, we get only positive values of x and y,
x=1, y=0.5
x=2, y=1.5
and hence x and y both are positive.

answer is C.

Q2.

total-T
Material's cost-M
Labor's cost- L
T=5= M+L

Statement 1-
T=3M
T=5=M+L=3M implies 2M=L
but nothing is give about profit, so Statement 1 is insufficient


Statement 2-
Profit greater than cost of labour, but nothing is given about the cost of labour. so Statement 2 is insufficient


Combining both Statements, we do have 2M=L, and profit is greater than cost of labour, M= 5/3=1.6, L=3.3=10/3 , total= 5 lakh=M+L
using the second statement, Profit is greater than labor cost, i.e greater 3.3 lakh so that does tell profit is greater than 1.5 lakh.

So the answer is C.

What's the OA?


Regards,
Neha
2028

@ Neha.. I think 5 is M+L+P.. "A construction company was paid a total of 5 Lakh "


Q2.

total-T
Material's cost-M
Labor's cost- L
T=5= M+L

Statement 1-
T=3M
T=5=M+L=3M implies 2M=L
but nothing is give about profit, so Statement 1 is insufficient

Regards,
Neha
2029
Hi!

Help needed with these 2 Ques:-

1. Are x and y both +ve?
a) 2x-2y = 1
b) x/y > 1

2. A construction company was paid a total of 5 Lakh for a project. the project's only costs were labour
and materials. Was the profit greater than 1.5 Lakh?
a) Total cost was 3 times the cost for materials.
b) Profit was greater than the cost for labour.

\m/

1. (a) Insufficient as x,y can be + as well as -
(b) Insufficient as x,y can be both + and can be both -ve but x > y.
a and b together: all the -ve values of x/y > 1 are eliminated by (a). So, I think "C" is the anwer..

2. (a) Insufficient
(b) Insufficient
a and b together: cost of material = x, cost of labour = 2x
Profit = cost of labout + K. this can or cannot be more than 1.5 lakh.
So, i'll go with E

statement 1:
============
x - y = 0.5.Nt suff x = -0.5 y = -1 x = 0 y = -0.5.Nt suff

statement 2:
============
x > y . x= 2.5 y = 2

I will go with option C

statement 1:
============
c = L + M c = 3M. Nt suff

statement 2:
============
P = L + x


Combining also we can't get a unique solution.
I will go with option E



Q1.

answer is C.

Q2.

So the answer is C.

What's the OA?


Regards,
Neha

Nipunbans Says
@ Neha.. I think 5 is M+L+P.. "A construction company was paid a total of 5 Lakh "



Hi All,

OAs are C and Not sure!

Both are 'real deal' gmat prep Qs. I too marked E for the 2nd one in the paper but I remember it showed that option as the wrong one! The OA was supposedly C.

But now M convinced so it has to be C and E.

Here is another one::

In xy plane, at what two points does the graph of y = (x+a)(x+b) intersect the x-axis?
a) a+b = -1
b) The graph intersects the y axis at (0,-6)

Regards!
2030
Hi All,

Here is another one::

In xy plane, at what two points does the graph of y = (x+a)(x+b) intersect the x-axis?
a) a+b = -1
b) The graph intersects the y axis at (0,-6)

Regards!


Statement 1-
a+b= -1
If a= -3 then b=2 or vice versa
then we get values of x,y as:
x=0, y= -6
x=1, y= -6
x=2, y= 4
On plotting the points, we see y=(x+a)(x+b) does intersect the x-axis.

To confirm, the line does intersect the x axis, take diff values of a and b, a= -4, b=3, then we get values of x, y as:
x=0, y= -12
x=1, y= -12
x=2, y= -10
x=3, y= -6
x=4, y= 0
x=5, y= 8
On plotting the points, we see y=(x+a)(x+b) does intersect the x-axis.

So Statement 1 is sufficient.

Statement 2-

The graph intersects the y axis at (0,-6).Put the given values in y=(x+a)(x+b), which gives ab= -6. now a and b can be either -1,6 or -6,1 OR 2,-3 or 3,-2 which gives two equations as y=(x-1)(x+6) and y=(x+3)(x-2).
Values of x and y for 1st eq are:
x=0, y= -6
x=1, y=0
x=2, y=8
On plotting the points, we see y=(x+a)(x+b) does intersect the x-axis.

And Values of x and y for 2nd eq are:
x=0, y= -6
x=1, y= -6
x=2, y= 4
On plotting the points, we see y=(x+a)(x+b) does intersect the x-axis.

So Statement 2 is also sufficient.

Hence Answer is D.
2031

To Bhavin for explaining the number line concept, Too Good Sirjee !!! You made one of the best generalisations. This makes my GMAT prep a lot more easier !! Thanks !!!

2032

What's th OA?

Hi All,

Here is another one::

In xy plane, at what two points does the graph of y = (x+a)(x+b) intersect the x-axis?
a) a+b = -1
b) The graph intersects the y axis at (0,-6)

Regards!



And yahaan itna san-nata kyun hai?
Why aren't people discussing and posting questions????
2033
What's th OA?



Waiting for few others to post the solution; regarding ur solution - I think u misinterpreted the Q. :)

Regards
2034
Hi All,


In xy plane, at what two points does the graph of y = (x+a)(x+b) intersect the x-axis?
a) a+b = -1
b) The graph intersects the y axis at (0,-6)

Regards!


A qaudratic equation is represented by a parabola ...
Hence we need the roots of the equation to find intersection pt at Y axis ...

We can use the general info of a quadratics ax^2+bx+c=0
Sum of roots = -b/a and prod of roots = c/a

Quad eqn of above sum translates to : x^2 +(a+b)x+ ab

St 1 : gives sum of roots only ...not suff..
St 2 : gives prod of roots only ...not suff

Combined : gives sum and prod of roots ...hence we can find the roots ...suff ...Ans C

Alternate explanation :
http://www.pagalguy.com/forum/gmat-a...sions-136.html (GMAT Data Sufficiency Discussions)
2035
Statement 1-
a+b= -1
If a= -3 then b=2 or vice versa
then we get values of x,y as:
x=0, y= -6
x=1, y= -6
x=2, y= 4
On plotting the points, we see y=(x+a)(x+b) does intersect the x-axis.

To confirm, the line does intersect the x axis, take diff values of a and b, a= -4, b=3, then we get values of x, y as:
x=0, y= -12
x=1, y= -12
x=2, y= -10
x=3, y= -6
x=4, y= 0
x=5, y= 8
On plotting the points, we see y=(x+a)(x+b) does intersect the x-axis.

So Statement 1 is sufficient.

Statement 2-

The graph intersects the y axis at (0,-6).Put the given values in y=(x+a)(x+b), which gives ab= -6. now a and b can be either -1,6 or -6,1 OR 2,-3 or 3,-2 which gives two equations as y=(x-1)(x+6) and y=(x+3)(x-2).
Values of x and y for 1st eq are:
x=0, y= -6
x=1, y=0
x=2, y=8
On plotting the points, we see y=(x+a)(x+b) does intersect the x-axis.

And Values of x and y for 2nd eq are:
x=0, y= -6
x=1, y= -6
x=2, y= 4
On plotting the points, we see y=(x+a)(x+b) does intersect the x-axis.

So Statement 2 is also sufficient.

Hence Answer is D.


Hey Neha ,
Question actually wants us to find the definitive points at which it cuts the Y axis ...only if we have the definitive points, are the statements sufficient ...

Individual statements actually gives us the liberty to plot infinite such parabolas ...i guess u misinterpreted the question as : whether or not the graph intersects the Y axis ..
2036
Waiting for few others to post the solution; regarding ur solution - I think u misinterpreted the Q. :)

Regards

Hey Neha ,
Question actually wants us to find the definitive points at which it cuts the Y axis ...only if we have the definitive points, are the statements sufficient ...

Individual statements actually gives us the liberty to plot infinite such parabolas ...i guess u misinterpreted the question as : whether or not the graph intersects the Y axis ..


You both are right, i misinterpreted the ques.
Thankyou for pointing that.
and thanks for explaining what the ques asked.


Regards,
Neha
2037
Hi!
2. A construction company was paid a total of 5 Lakh for a project. the project's only costs were labour
and materials. Was the profit greater than 1.5 Lakh?
a) Total cost was 3 times the cost for materials.
b) Profit was greater than the cost for labour.

\m/

Hi All,

OAs are C and Not sure!

Both are 'real deal' gmat prep Qs. I too marked E for the 2nd one in the paper but I remember it showed that option as the wrong one! The OA was supposedly C.

But now M convinced so it has to be C and E.

Regards!


Justification on why C should be the right answer.
Stmt 1: M + L = 3M => M = L/2
=> M + L + P = 5
=> L/2 + L + P = 5
=> 3L/2 + P = 5

Now, even if we assume, that P = L, then also, we get
=> 3P/2 + P = 5
=> 5P/2 = 5
=> P = 2

But, as per statement 2, P > L, indicating that P has to be greater than 2 (and L lesser than 2.)
Hence, C.
Hope that clarifies.
2038

I am struggling with my basics here. Somebody please help me on what could be wrong in this.
I have two interpretations of statement x/y > 1 :
1. x > y, and
2. that x and y both have same signs, such that the whole term turns positive and is as well greater than 1.

If both these interpretations are correct, then we are in the soup. Consider this.
x = 2 and y = -3
Though 2 > -3, but signs of both these numbers are different....

I am sure I am not in:drinking:mood.

2039
Justification on why C should be the right answer.
Stmt 1: M + L = 3M => M = L/2
=> M + L + P = 5
=> L/2 + L + P = 5
=> 3L/2 + P = 5

Now, even if we assume, that P = L, then also, we get
=> 3P/2 + P = 5
=> 5P/2 = 5
=> P = 2

But, as per statement 2, P > L, indicating that P has to be greater than 2 (and L lesser than 2.)
Hence, C.
Hope that clarifies.


Cnt see any mistake really :)

I am struggling with my basics here. Somebody please help me on what could be wrong in this.
I have two interpretations of statement x/y > 1 :
1. x > y, and
2. that x and y both have same signs, such that the whole term turns positive and is as well greater than 1.

If both these interpretations are correct, then we are in the soup. Consider this.
x = 2 and y = -3
Though 2 > -3, but signs of both these numbers are different....

I am sure I am not in:drinking:mood.


x/y >1 surely has 2 interpretations::

x/y - 1 > 0

x-y /y > 0

If y> 0 then x>y... so both +ve
If y
x = 2 y= -3 doesnt give x/y > 1.. Wht do u intend to mean ? :)

Regards!
2040
I am struggling with my basics here. Somebody please help me on what could be wrong in this.
I have two interpretations of statement x/y > 1 :
1. x > y, and
2. that x and y both have same signs, such that the whole term turns positive and is as well greater than 1.

If both these interpretations are correct, then we are in the soup. Consider this.
x = 2 and y = -3
Though 2 > -3, but signs of both these numbers are different....

I am sure I am not in:drinking:mood.


Hey Ankit ...I think i have understood what u r wanting to say ...
Statement in bold is incorrect ...let me help point out the flaw...

x/y >1 is not same as x>y ....here u r multiplying by y on both sides...since y is a variable u dont know the sign associated with it ...So if y>0 ...multiplying both sides by y leaves the sign unchanged...
But, if y