[alchemist-mba]

Originally Posted by ankitgarg20

Question from GMATprep

If n and p are integers,is p>0
1) n+1>0
2) np>0

My take 'C'.

stmt 1 : n+1 > 0 => n > -1 => n = 0, 1, 2, 3..... - says nothing about P - insufficeint.

stmt 2: np> 0 => n and p can be either (+) ve or (-) ve.. so P can be either (+) ve or (-) ve.... insufficient.

Combine both statements... np > 0 and n = 0,1,2,3.....

so n & p should be (+) ve.....

[ankitgarg20]

Originally Posted by alchemist-mba

My take 'C'.

stmt 1 : n+1 > 0 => n > -1 => n = 0, 1, 2, 3..... - says nothing about P - insufficeint.

stmt 2: np> 0 => n and p can be either (+) ve or (-) ve.. so P can be either (+) ve or (-) ve.... insufficient.

Combine both statements... np > 0 and n = 0,1,2,3.....

so n & p should be (+) ve.....

yea the OA is C
I overlooked the 'integer' part
thanks

[karedia.a]

in xy plane at what two points does the graph of y=(x+a)(x+b) intersects the x-axis.
1) a+b= -1
2) the graph intersects the y-axis at (0,-6)

the answer is c
Please anyone can explain me the reason why the answer is c.I will be pleased to see some helping me to solve the problem as i have tried this sum for 10 times and i cannot understand the question itself.

[jha16june]

Originally Posted by karedia.a

in xy plane at what two points does the graph of y=(x+a)(x+b) intersects the x-axis.
1) a+b= -1
2) the graph intersects the y-axis at (0,-6)

the answer is c
Please anyone can explain me the reason why the answer is c.I will be pleased to see some helping me to solve the problem as i have tried this sum for 10 times and i cannot understand the question itself.

The answer is indeed C.
The question asks what are the zeros of the equation: y=(x+a)(x+b). Obviously y is 0 at x=-a, and -b. So the question is can we find the values of a and b.
stmt1: gives one equation, not sufficient.
stmt2: (0, -6) satisfies the equation y=(x+a)(x+b), so from here we get another relation in a and b as ab=-6.

So now we have 2 equations in 2 unknowns so it can be solved for a and b. So the answer is C.

[*arch*]

Are x and y both positive?

(1) 2x - 2y = 1
(2) x/y > 1

[mockingabird]

Originally Posted by *arch*

Are x and y both positive?

(1) 2x - 2y = 1
(2) x/y > 1

from 1

x-y = 1/2

x=-1
y=-1.5

x=1
y=0.5

x=3/4
y=-1/4

inconclusive

x>y
x=1
y=-5

x=4
y=2

inconclusive

both together
x=1
y=o.5

x=3/4
y=-1/4

still inconclusive
Ans E

[*arch*]

Hey.. i chose (E) as well.. but the OA is (C). Can someone plz help?!?!

This is one of the questions from GMAT Prep.

Originally Posted by mockingabird

from 1

x-y = 1/2

x=-1
y=-1.5

x=1
y=0.5

x=3/4
y=-1/4

inconclusive

x>y
x=1
y=-5

x=4
y=2

inconclusive

both together
x=1
y=o.5

x=3/4
y=-1/4

still inconclusive
Ans E

[ashishjha100]

Originally Posted by *arch*

Are x and y both positive?

(1) 2x - 2y = 1
(2) x/y > 1

My pick is C......

1. 2x - 2y = 1 ==> x-y=1/2
x=1 y=1/2 x-y=1/2
x=1/2 y=0 x-y=1/2 so not sufficient.....

2.x/y>1
not sufficient b/c x&y can be both +ve or -ve.

combining we can eliminate counter example in st1 that x=1/2 & y=0 since x&y should be both +ve or -ve. so C

correct me if i'm wrong.......

[*arch*]

Another one from GMAT Prep:-

If x is a positive number less than 10, is z greater than the average (arithmetic mean) of x and 10?

1) On the number line, z is closer to 10 than it is to x.
2) z = 5x

[ashishjha100]

Originally Posted by mockingabird

from 1

x-y = 1/2

x=-1
y=-1.5

x=1
y=0.5

x=3/4
y=-1/4

inconclusive

x>y
x=1
y=-5

x=4
y=2

inconclusive

both together
x=1
y=o.5

x=3/4
y=-1/4

still inconclusive
Ans E

x>y
x=1
y=-5

mockingabird,
ur given example is not valid.......it doesnot give x/y>1