Can someone give some explanation for the following

Question

Can someone give some explanation for the following questions please

hobbit · Answer

can you inline the question? (i can't open attachment properly)

lali · Answer

hope this helps

lfox2 · Answer

For question 2 I would go for C, because you can derive equations from both and then combine them to work out the % of M = Managers and D = Directors

For question 2 I would C 

What are the OA?

enola · Answer

For question 3 regarding the 40 meter string, my answer is D. Since the question asks for total area in term of r, we need to express the side of the square in term of r. We know the perimeters of the circle and the square are from the 40 meter string. thus, Circumference of the Circle = 40 - perimeter of the square ,<=> 2(pi)r = 40 - 4s ( s being the side of the square.

Put s on one side and solve in term of r we have s = 10 - (pi*r)/2.

So, the total area = (pi)*r^2 + (10 - pi*r/2)^2 => D

For question 2 regarind the managers and directors, my answer is E
(1) Insuff since all we know is Sum(M)/M= Sum(M+D)/ M+D -5000

With Sum(M): total salaries of all managers.
M: number of manager.
Sum (D): total salaries of all Directors.
D: number of director.

(2) similar argument Sum(D) / D = Sum (M+D)/M+D +15000
Insuff

(1) + (2): Sum(m)/m = Sum (D)/D -20000. so we only know the relationship of the average. Insuff to find the percentage of directors=> E


For question 1 regarding the triangle, my answer is C
(1) Insuff because we only know the RQ = RS and thus the two angles equal to each other.
(2) Insuff with similar argument.
(1) + (2): connect S and P.
Angle RQS = part of x + part of RPT since RQS is the outside angle. 
Angle SUT = part of x + part of RPT for the same reason.
so RQS + SUT = x +90.
we also know that :
RQS = RSQ
SUT = UST
and RSQ + UST + x = 180.
from these 2x = 90 suff to find x => C

lali · Answer

Thanks for the help. The OA are 1. e 2.c 3.c enola u'r explanation regarding the square and the circle really helped me understand what i was doing wrong.

but lfox2 can u pls explain incase of the manager director question how u came up with c. ?

lfox2 · Answer

Lali,

I have reposted the managers and directors questions, since I could not prove out the answer C.

For the first question, which is definitly a 700+ question, what was your qunat score? Over 45? 

I worked it out as follows with the help of a clever person:

C = Circumference of the circle and S = the four side of the square

C + S = 40

C = 2pir (Circumference)

So 2pir + s = 40

S = 40 - 2pir

Area of a circle = pir^2 and area of square = s^2 / 16

Plug in 40 - 2pi^2 into S to give you:

(40-2pi^2)^2 / 16 - At this point my head was hurting!!

If there was an answer choice such as

pir^2 + ((40-2pi^2)^2 / 16) then we would be finished, but there isn't

So,

(40-2pi^2)(40-2pi^2) / 16 BECOMES:
2(20-2pi^2) * 2(20-2pi^2) / 16 BECOMES (Cancel out the 2's)

(20-2pi^2) * (20-pi^2) / 4 BECOMES

400 - 40pir + pi^2 * r^2 / 4 BECOMES (Cancel out the 4)

100 - 10pir + (1/4 * pi^2 * r^2)

If you look at the last equation this is really

(10 - 1/2pir)^2 which can be found in E, hence E is the answer

Can someone give some explanation for the following

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