Can't Figure out.....

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Can't Figure out.....

by phoenix9801 » Thu Jan 28, 2010 10:13 am
Hi I need help to figure out... since I am not too sure about them. Hope it not too much nor confusing. Would greatly appreciate it..

1- What is the value of a ?

(1) a + b = 7 + b
(2) a2 = 49

a) Statement (1) BY ITSELF is sufficient to answer the question, but statement (2) by itself is not.
b)Statement (2) BY ITSELF is sufficient to answer the question, but statement (1) by itself is not.
c)Statements (1) and (2) TAKEN TOGETHER are sufficient to answer the question, even though NEITHER statement BY ITSELF is sufficient.
d)EITHER statement BY ITSELF is sufficient to answer the question.
e)Statements (1) and (2) TAKEN TOGETHER are NOT sufficient to answer the question, requiring more data pertaining to the problem.

______________________________________________________________________________________________

2-A household subscribes to a calling plan which charges 10 cents per minute for all domestic telephone calls and 35 cents per minute for all international calls. If 180 minutes of phone calls were made from the household, how many of these minutes were international calls?

(1) The total cost of domestic calls made from the household was $10.00.
(2) The total cost of all telephone calls from the household was $38.00.

a) Statement (1) BY ITSELF is sufficient to answer the question, but statement (2) by itself is not.
b)Statement (2) BY ITSELF is sufficient to answer the question, but statement (1) by itself is not.
c)Statements (1) and (2) TAKEN TOGETHER are sufficient to answer the question, even though NEITHER statement BY ITSELF is sufficient.
d)EITHER statement BY ITSELF is sufficient to answer the question.
e)Statements (1) and (2) TAKEN TOGETHER are NOT sufficient to answer the question, requiring more data pertaining to the problem.

______________________________________________________________________________________________

3-What is the value of y^2 ?

(1) ( x + 3)( x - 3) = x^2 - y^2
(2) ( x + 3)( x + 3) = x^2 + y^2

a) Statement (1) BY ITSELF is sufficient to answer the question, but statement (2) by itself is not.
b)Statement (2) BY ITSELF is sufficient to answer the question, but statement (1) by itself is not.
c)Statements (1) and (2) TAKEN TOGETHER are sufficient to answer the question, even though NEITHER statement BY ITSELF is sufficient.
d)EITHER statement BY ITSELF is sufficient to answer the question.
e)Statements (1) and (2) TAKEN TOGETHER are NOT sufficient to answer the question, requiring more data pertaining to the problem.

______________________________________________________________________________________________

4-Is x > y ?

(1) x^2 > y^2
(2) 3 x - 7 > - 3

a) Statement (1) BY ITSELF is sufficient to answer the question, but statement (2) by itself is not.
b)Statement (2) BY ITSELF is sufficient to answer the question, but statement (1) by itself is not.
c)Statements (1) and (2) TAKEN TOGETHER are sufficient to answer the question, even though NEITHER statement BY ITSELF is sufficient.
d)EITHER statement BY ITSELF is sufficient to answer the question.
e)Statements (1) and (2) TAKEN TOGETHER are NOT sufficient to answer the question, requiring more data pertaining to the problem.

______________________________________________________________________________________________

5-Jack has a jar full of dimes and nickels, the total value of which is $10.00. What is the value of the nickels in the jar?

(1) There are exactly 65 dimes in the jar.
(2) There are 5 more nickels than dimes in the jar.

a) Statement (1) BY ITSELF is sufficient to answer the question, but statement (2) by itself is not.
b)Statement (2) BY ITSELF is sufficient to answer the question, but statement (1) by itself is not.
c)Statements (1) and (2) TAKEN TOGETHER are sufficient to answer the question, even though NEITHER statement BY ITSELF is sufficient.
d)EITHER statement BY ITSELF is sufficient to answer the question.
e)Statements (1) and (2) TAKEN TOGETHER are NOT sufficient to answer the question, requiring more data pertaining to the problem.

______________________________________________________________________________________________


6- Edmund works at a constant rate and assembles 18 clocks in 3 hours. How much less time would be needed to assemble the same number of clocks if both Edmund and Heinrich were working simultaneously and Heirich works at a constant rate and assembles 18 clocks in H hours where H > 0?

(1) Both Edmund and Heinrich assemble the same number of clocks every hour.
(2) It takes Edmund and Heinrich, working simultaneously, half as long to assemble the clocks as it takes Heinrich working alone.

a) Statement (1) BY ITSELF is sufficient to answer the question, but statement (2) by itself is not.
b)Statement (2) BY ITSELF is sufficient to answer the question, but statement (1) by itself is not.
c)Statements (1) and (2) TAKEN TOGETHER are sufficient to answer the question, even though NEITHER statement BY ITSELF is sufficient.
d)EITHER statement BY ITSELF is sufficient to answer the question.
e)Statements (1) and (2) TAKEN TOGETHER are NOT sufficient to answer the question, requiring more data pertaining to the problem.
Source: — Data Sufficiency |

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by thephoenix » Thu Jan 28, 2010 7:27 pm
phoenix9801 wrote:Hi I need help to figure out... since I am not too sure about them. Hope it not too much nor confusing. Would greatly appreciate it..

1- What is the value of a ?

(1) a + b = 7 + b
(2) a2 = 49

a) Statement (1) BY ITSELF is sufficient to answer the question, but statement (2) by itself is not.
b)Statement (2) BY ITSELF is sufficient to answer the question, but statement (1) by itself is not.
c)Statements (1) and (2) TAKEN TOGETHER are sufficient to answer the question, even though NEITHER statement BY ITSELF is sufficient.
d)EITHER statement BY ITSELF is sufficient to answer the question.
e)Statements (1) and (2) TAKEN TOGETHER are NOT sufficient to answer the question, requiring more data pertaining to the problem.

IMO A
s1) cancelling b bth side gives a=7
suff
s2) take rut bth side
+-a=7--->a=7 or -7
insuff.....

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by thephoenix » Thu Jan 28, 2010 7:32 pm
phoenix9801 wrote:Hi I need help to figure out... since I am not too sure about them. Hope it not too much nor confusing. Would greatly appreciate it..


2-A household subscribes to a calling plan which charges 10 cents per minute for all domestic telephone calls and 35 cents per minute for all international calls. If 180 minutes of phone calls were made from the household, how many of these minutes were international calls?

(1) The total cost of domestic calls made from the household was $10.00.
(2) The total cost of all telephone calls from the household was $38.00.

a) Statement (1) BY ITSELF is sufficient to answer the question, but statement (2) by itself is not.
b)Statement (2) BY ITSELF is sufficient to answer the question, but statement (1) by itself is not.
c)Statements (1) and (2) TAKEN TOGETHER are sufficient to answer the question, even though NEITHER statement BY ITSELF is sufficient.
d)EITHER statement BY ITSELF is sufficient to answer the question.
e)Statements (1) and (2) TAKEN TOGETHER are NOT sufficient to answer the question, requiring more data pertaining to the problem.

IMO D

from q stem we get one eqn
x+y=180(x=no of domestic calls and y=no. of int calls)

s1)0.1 x =10
x=100 therefore y=80
suff
s2)0.1x+0.35y=38
x+y=180
solving
y=80
suff
hence D

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by thephoenix » Thu Jan 28, 2010 7:41 pm
phoenix9801 wrote:Hi I need help to figure out... since I am not too sure about them. Hope it not too much nor confusing. Would greatly appreciate it..


3-What is the value of y^2 ?

(1) ( x + 3)( x - 3) = x^2 - y^2
(2) ( x + 3)( x + 3) = x^2 + y^2

a) Statement (1) BY ITSELF is sufficient to answer the question, but statement (2) by itself is not.
b)Statement (2) BY ITSELF is sufficient to answer the question, but statement (1) by itself is not.
c)Statements (1) and (2) TAKEN TOGETHER are sufficient to answer the question, even though NEITHER statement BY ITSELF is sufficient.
d)EITHER statement BY ITSELF is sufficient to answer the question.
e)Statements (1) and (2) TAKEN TOGETHER are NOT sufficient to answer the question, requiring more data pertaining to the problem.

IMO A

s1)x^2-9=x^2-y^2-------->-y^2=-9------->y^2=9
suff

s2) solving eqn
we get y^2-2xy-9=0
two variable one eqn so we can't get y^2
insuff...

hence A
OA pls

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by harsh.champ » Mon Feb 01, 2010 2:30 am
First of all,your method of solving the first 3 questions is correct and you must be absolutely confident about them.

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by harsh.champ » Mon Feb 01, 2010 2:37 am
Now,for the 4th question
4-Is x > y ?

(1) x^2 > y^2
(2) 3 x - 7 > - 3

a) Statement (1) BY ITSELF is sufficient to answer the question, but statement (2) by itself is not.
b)Statement (2) BY ITSELF is sufficient to answer the question, but statement (1) by itself is not.
c)Statements (1) and (2) TAKEN TOGETHER are sufficient to answer the question, even though NEITHER statement BY ITSELF is sufficient.
d)EITHER statement BY ITSELF is sufficient to answer the question.
e)Statements (1) and (2) TAKEN TOGETHER are NOT sufficient to answer the question, requiring more data pertaining to the problem.

__________________

From the (1)statement you cant figure out if x >y as x [or/and] y can be negative.
From the (2)statement we get that x>4/3,but we can't compute any value of y.
Taking both the statements together, x^2>y^2.....which implies that y^2< 16/9
From the number line ,we can thus compute that x>4/3 and -4/3<y<4/3 ...
Thus x is always greater than y...Hence,(c) is the answer.

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by harsh.champ » Mon Feb 01, 2010 2:48 am
For the 5th question,
5-Jack has a jar full of dimes and nickels, the total value of which is $10.00. What is the value of the nickels in the jar?

(1) There are exactly 65 dimes in the jar.
(2) There are 5 more nickels than dimes in the jar.

a) Statement (1) BY ITSELF is sufficient to answer the question, but statement (2) by itself is not.
b)Statement (2) BY ITSELF is sufficient to answer the question, but statement (1) by itself is not.
c)Statements (1) and (2) TAKEN TOGETHER are sufficient to answer the question, even though NEITHER statement BY ITSELF is sufficient.
d)EITHER statement BY ITSELF is sufficient to answer the question.
e)Statements (1) and (2) TAKEN TOGETHER are NOT sufficient to answer the question, requiring more data pertaining to the problem.

______________



Statement 1:If there are 65 dimes,it amounts to 6.50 dollars...hence rest $3.50 are in nickels.
Statement 2:Suppose dimes=x ,then nickels=x+5..hence total dollar value is (x/10)+(x+5/20)
That means (x/10)+(x+5/20) should be equal to 10.
Hence option (d) is the correct answer.

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by harsh.champ » Mon Feb 01, 2010 2:54 am
For the 6th question,
6- Edmund works at a constant rate and assembles 18 clocks in 3 hours. How much less time would be needed to assemble the same number of clocks if both Edmund and Heinrich were working simultaneously and Heirich works at a constant rate and assembles 18 clocks in H hours where H > 0?

(1) Both Edmund and Heinrich assemble the same number of clocks every hour.
(2) It takes Edmund and Heinrich, working simultaneously, half as long to assemble the clocks as it takes Heinrich working alone.

a) Statement (1) BY ITSELF is sufficient to answer the question, but statement (2) by itself is not.
b)Statement (2) BY ITSELF is sufficient to answer the question, but statement (1) by itself is not.
c)Statements (1) and (2) TAKEN TOGETHER are sufficient to answer the question, even though NEITHER statement BY ITSELF is sufficient.
d)EITHER statement BY ITSELF is sufficient to answer the question.
e)Statements (1) and (2) TAKEN TOGETHER are NOT sufficient to answer the question, requiring more data pertaining to the problem.


______________
Statement 1:According to the statement,H=3
Statement 2:This statement is the same as statement 1 ,just the presentation is different,hence H=3.
Thus,option (d) is the answer.