Manhattan No. properties

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by selango » Sat May 29, 2010 2:45 am
IMO E

x^2<=2x

Hence we need to prove whether X<=2

first statement tell x>0,not sufficient as x can be any numbers like 1,2 or 3

second statement tell x<=3,not sufficient,same reason as above

Even if combine x>0 and x<=3,x can be any number 1,2 or 3.still not sufficient.

So E..what is OA

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by vijju » Sat May 29, 2010 3:33 am
IMO... C

x>0 means 1,2,3....

1 and 2 when used the answer is Yes and when we use any number more than 2 its No

So insufficient.

x<3

same goes with Choice B as well 1 and 2 satisfy but any negative number does not satisfy.

When combined both A and B x>0 and x<3 the only optons left are 1 and 2 which satisfy the condition above the question.

So C

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by raviki8208 » Sat May 29, 2010 4:02 am
vijju wrote:IMO... C

x>0 means 1,2,3....

1 and 2 when used the answer is Yes and when we use any number more than 2 its No

So insufficient.

x<3

same goes with Choice B as well 1 and 2 satisfy but any negative number does not satisfy.

When combined both A and B x>0 and x<3 the only optons left are 1 and 2 which satisfy the condition above the question.

So C
Hi Vijju,
x need not be an integer. so, answer would be E.

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by clock60 » Sat May 29, 2010 4:03 am
nikhilkatira wrote:Is x^2 <= 2x ?

1) x > 0
2) x < 3
E for me

is x^2-2x<=0
x(x-2)<=0
or 0<x<2
from both we know that 0<x<3
but as value of x does`t fix with integers x can be fraction between 2 and 3

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by nikhilkatira » Sat May 29, 2010 5:16 am
selango wrote:IMO E

x^2<=2x

Hence we need to prove whether X<=2

first statement tell x>0,not sufficient as x can be any numbers like 1,2 or 3

second statement tell x<=3,not sufficient,same reason as above

Even if combine x>0 and x<=3,x can be any number 1,2 or 3.still not sufficient.

So E..what is OA
OA is E

i want to know how can you reduce x^2<=2x to x<=2 because we don't know whether x is +ve or -ve ?
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by odod » Sat May 29, 2010 7:53 am
even if X is a fraction between 2 and 3 (such as 4/3) then can't we solve the problem by saying "yes" to answer choice c?

If x = 4/3 then

16/9<= 24/9 which would allow us to answer YES

Expert please help!
ODOD

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by odod » Sat May 29, 2010 7:54 am
even if X is a fraction between 2 and 3 (such as 4/3) then can't we solve the problem by saying "yes" to answer choice c?

If x = 4/3 then

16/9<= 24/9 which would allow us to answer YES

Expert please help!
ODOD

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by selango » Sat May 29, 2010 8:07 am
what is the source of this question?


Usually it ll be mentioned whether variable is integer or not..

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by nikhilkatira » Sat May 29, 2010 10:16 am
selango wrote:what is the source of this question?


Usually it ll be mentioned whether variable is integer or not..
Manhattan Number Properties Book
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by nikhilkatira » Sat May 29, 2010 10:19 am
odod wrote:even if X is a fraction between 2 and 3 (such as 4/3) then can't we solve the problem by saying "yes" to answer choice c?

If x = 4/3 then

16/9<= 24/9 which would allow us to answer YES

Expert please help!
4/3 = 1.33 which is not between 2 and 3
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