DATA SUFFICIENCY 3 problems

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DATA SUFFICIENCY 3 problems

by ddm » Wed Jul 30, 2008 11:18 am
1.In isosceles triangle RST what is the measure of angle R?

1. The measure of angle T is 100
2. The measure of angle S is 40

A. Statement 1
B. Statement 2
C. Both
D. Each Statement alone
E. None



2. On a sight seeing tour, the ration of number of women to children was 5 to 2. what was the number of men in the sight seeing tour?

1. On the sight seeing tour, the ratio of number of children to number of men was 5 to 11
2. Number of women on the sight seeing tour was less then 30.

A. Statement 1
B. Statement 2
C. Both
D. Each Statement alone
E. None


3.What is the average(arithmetic mean) of 11 consecutive integers?

1. the average of the first 9 integers is 7
2. the average of the last 9 integers is 9


A. Statement 1
B. Statement 2
C. Both
D. Each Statement alone
E. None
Source: — Data Sufficiency |

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by parallel_chase » Wed Jul 30, 2008 3:02 pm
From next time kindly post only one question per post.

Ques1

Statement I
R+S+T = 180
2x+T=180=>x=40 Sufficient (we cant have 2, 100 degree angles)

Statement II
R+S+T = 180
40+40+100 =180
70+70+40 =180 Insufficient

Hence A.

Ques 2 W:C = 5:2

Statement I
C:M = 5:11
Insufficient because we dont know the number of either women or children or men or the total number people who went for the sight seeing tour.

Statement II
women were less than 30. same reasoning as above, women could be 25, 20 10 or 5 Insufficient.

Combining Statement I & II absolutely nothing more can be deduced.

Hence E.


Ques 3
Average of first 11 integers? [x+(x+1)+(x+2)+.....+(x+10)]/11 =?

You can rephrase the question as what is the value of x?

Statement I
average of first 9 integers is 7
[x+(x+1)+(x+2)+.....+(x+8)]/9 = 7
You can easily find the value of x
Sufficient.

Statement II
average of last 9 integers is 9
[(x+2)+(x+3)+.....+(x+10)]/9 =9
You can easily find the value of x
Sufficient.

Hence D.

What are the OAs?

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by ddm » Wed Jul 30, 2008 3:40 pm
hey...
thanks a lot for ur help.
i had solved these question on the GMATPrep CD.
as u might know...they just mention if the answer is correct or incorrect n then show the correct answer...they don't have any explanations

So, the 1st and 3rd answer given to you are correct.
But the 2nd answer shown on the GMATPrep was choice C.

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by parallel_chase » Wed Jul 30, 2008 3:58 pm
Sorry about that. These silly mistakes are killing me. The answer is indeed C.

W:C => 5:2

Statement I
C:M => 5:11

Therefore, W:C:M => 25:10:12 (this you can calculate if you know ratios, let me know if you cant.)

Anyways here it is, Let total number of women and children be 70, I chose 70 for easier calculations. We will have 50 women and 20 children according to the ratio 5:2.

C:M => 5:11

There are 20 children, you can calculate the combined ratio by following method:

20/x = 5/11
x = 24

Combined ratio W:C:M => 50:20:24=> 25:10:12 (Let me know if you still face any problem with this)

Statement II

Women are less than 30

Combining I & II

Women will always be in multiple of 25.

Therefore, there are 25 women, 10 children & 12 men.

Hence C.

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by hijja » Thu Jul 31, 2008 4:55 am
Just to correct a small mistake..
The ratio W:C:M should be 25:10:22 instead of 25:10:12
Answer remains C though..

:)

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by parallel_chase » Thu Jul 31, 2008 7:37 am
hijja wrote:Just to correct a small mistake..
The ratio W:C:M should be 25:10:22 instead of 25:10:12
Answer remains C though..

:)
You are absolutely right. 50:20:44=>25:10:22


Thanks