Multiple questions..DS + PS

[khizarj]

1) In a certain class 72% of the male students and 80% of the female students have applied to college. What fraction of the students in the class are male?

1. 840 students in senior class
2. 75% of the students in the senior class have applied to college

OE B


2) Two triangls A and B have the same angle measures. Area of B is twice the area of A. One side of A is 's' and corresponding side of B is 'S', what is S =

OE [spoiler]sqrt(2)*s[/spoiler]


3) What is the greatest possible area of a triangular region with one vertex at the center of a circle of radius 1 and the other two vertices on the circle

OE [spoiler]1/2[/spoiler]


4) If x is not equal to -y, is (x - y)/(x + y) > 1?

1. x > 0
2. y < 0

OE E


5) In a certain year the UN's total expenditures were $1.6 billion. Of this amount, 67.8 % was paid by the 6 highest-contributing countires, and the balance was paid by the remainin 153 countries. Was Country X among the 6 highest-contributing countries?

1. 56% of the total expenditures was paid by the 4 highest-contributing countries, each of which paid more than Country X.
2. Country X paid 4.8 % of the total expenditures.

OE E


6) If 500 is the multiple of 100 that is closest to x and 400 is the multiple of 100 that is closest to y, which multiple of 100 is closest to x + y?

1. x < 500
2. y < 400

OE E

I don't even understand what this question is asking



7) If k is a positive integer, is k the square of an integer?

1. k is divisble by 4.
2. k is divisible by exactly four different prime numbers.

OE E


8) If (-) denotes one of two arithmetic operations, addition or multiplication, and if k is an integer, what is the value of 3 (-) k?

1. 2(-)k = 3
2. 1(-)0 = k

OE A

(My thinking: (1.) 2+1 = 3, therefore k = 1. So 3(-)k = 3+1 or 3*1. Insufficient(2.) k = 1 or 0. So 3(-)k=4 or 0 Insufficient. Together also insufficient)


9) Is |x| = y - z?

1. x + y = z
2. x < 0

OE C

[vikram4689]

1. B

0.75 (m + f) = 0.72 m + 0.8 f ......find f/m
we want m/(m+f) => 1/(1+f/m)

2. Area for S/ Area for s = S*S/s*s .....property of similar triangles.

3. Can be easily solved if options are given ....1/2*b*h

4. should be C....
(x - y)/(x + y)
=> (1-y/x)/(1+y/x)
=> (1+ +ve)/(1- +ve) ....always >1

5. I - 4 were higher than X but dont know where X stand among all other
II - X paid 4.8% but dont know how much other paid.
I & II - (67.8-56 = 11.8), 11.8% was paid by 5 & 6 highest paying nations now we do not know whether X was in that list. Note if difference comes out to be less than 9.6% then X would always be among highest paying nations.

6. It is saying that 500 is multiple of 100 closest to X. Lets say X is 525 or 475 but it has to be b/w 451 and 550.
Now we need X and Y so A & B can never be ans.
x < 500 can be 451 or 499
y < 400 can be 351 or 399

x+y varies from 802 to 898
802 - closest to 800
898 - closest to 900 . Hence E.

7. Clearly E
I - 24 (not sq. of integer) is divisible by 4
36 (sq. of integer) is divisible by 4
II - 2*3*5*7 .not a sq. but 2*2*3*3*5*5*7*7 is a sq.

Using I & II would yield same result.Hence E.

8. You changed the eqn in I. Logic to this question is that 0 is an integer.

9. I - use x,y,z as 2,1,3 and for one options take y=z.....INSUFF.
II - x<0 dosent give any info on y & z
I & II - will yield the answer than given eqn is ALWAYS equal.

[khizarj]

3. Given that one vertex is on center that means we know its an isocoles triangle with the two equal sides of 1 and 1. How can we find the area? We don't even know the angles.

4. I thought so too but the original answer is from GMAC..so?

8. i don't understand. Could you explain from the beginning. WHat I understood from teh question is that, either 2 * k = 3 OR 2 + k = 3. Therefore k is either 1.5 OR 1, but since k is an integer, k must be 1. Now, we need to find 3 (-) k, which mean, either 3 + k or 3 * k. That is either 3*1 or 3+1, which is either 3 or 4, therefore 1. is insufficient?????