Percentage Problem
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Can somebody help me with this GMATprep question or provide link if it exist already?
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I have come up with a very easy way to do questions like these.
Basically, remember this as a rule: if you have the arithmetic means for X, Y and X&Y, you can a) know which of them has a higher weight, and b) the ratio X:Y. Plot the averages on a number line.
---X----(X&Y)---------Y
Basically, if (X&Y) is closer to X, X has a greater weight.
The ratio X:Y is Y-(X&Y):X-(X&Y)
[NOTE: The calculation uses AVERAGES of Y, X&Y and X]
Basically, remember this as a rule: if you have the arithmetic means for X, Y and X&Y, you can a) know which of them has a higher weight, and b) the ratio X:Y. Plot the averages on a number line.
---X----(X&Y)---------Y
Basically, if (X&Y) is closer to X, X has a greater weight.
The ratio X:Y is Y-(X&Y):X-(X&Y)
[NOTE: The calculation uses AVERAGES of Y, X&Y and X]
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Using the above prescribed method:
The question gives us the following information:
Am=9.8
Af=9.1
(The average number of years of work experience for the male/female employees)
And asks us to calculate the M:F ratio.
Statement 1: There are 52 make employees at the company. This doesn't tell us anything. Definitely not sufficient to calculate the M:F ratio. INSUFFICIENT.
Lets look at Statement 2. Amf=9.3 (The average number of work experience for all employees)
Lets plot this on a number line.
9.1(Af)--9.3(Amf)-----9.8(Am)
<----0.2----><-----0.5----->
M:F
2:5
SUFFICIENT. The answer should be B.
The question gives us the following information:
Am=9.8
Af=9.1
(The average number of years of work experience for the male/female employees)
And asks us to calculate the M:F ratio.
Statement 1: There are 52 make employees at the company. This doesn't tell us anything. Definitely not sufficient to calculate the M:F ratio. INSUFFICIENT.
Lets look at Statement 2. Amf=9.3 (The average number of work experience for all employees)
Lets plot this on a number line.
9.1(Af)--9.3(Amf)-----9.8(Am)
<----0.2----><-----0.5----->
M:F
2:5
SUFFICIENT. The answer should be B.
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Could you Pleaseeeeeeeee tell me how could you solve for number of employees when all these averages are about male and female average work experience?!!shanrizvi wrote:Using the above prescribed method:
The question gives us the following information:
Am=9.8
Af=9.1
(The average number of years of work experience for the male/female employees)
And asks us to calculate the M:F ratio.
Statement 1: There are 52 make employees at the company. This doesn't tell us anything. Definitely not sufficient to calculate the M:F ratio. INSUFFICIENT.
Lets look at Statement 2. Amf=9.3 (The average number of work experience for all employees)
Lets plot this on a number line.
9.1(Af)--9.3(Amf)-----9.8(Am)
<----0.2----><-----0.5----->
M:F
2:5
SUFFICIENT. The answer should be B.
Also, the ration for males to females seems should be 5:2 not 2:5 ?
Thanks a lot
- viju9162
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A(m) = 9.8
A(f) = 9.1
n(m)/n(f) = ?
(1)
n(m) = 52 - not sufficient
(2)
X = n(m), Y = n(f)
9.3 = 9.8*X + 9.1*Y/ X+Y
You can get the ratio .. hence B is sufficient
A(f) = 9.1
n(m)/n(f) = ?
(1)
n(m) = 52 - not sufficient
(2)
X = n(m), Y = n(f)
9.3 = 9.8*X + 9.1*Y/ X+Y
You can get the ratio .. hence B is sufficient
"Native of" is used for a individual while "Native to" is used for a large group
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viju9162. Why did you put x and y in the numerator? seems to me that the average years of experience for both will be (9.1 + 9.8)/(x + y)= 9.3 in other words, why 9.1Y + 9.8X ?
- viju9162
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If you look the average formula
Avg = Sum of all the numbers / total numbers.
Sum of all the numbers in this case will be Avg(M) * total number(M) ..hence in the numerator, we take 9.1Y + 9.8X..
I hope this helps ...
Avg = Sum of all the numbers / total numbers.
Sum of all the numbers in this case will be Avg(M) * total number(M) ..hence in the numerator, we take 9.1Y + 9.8X..
I hope this helps ...
"Native of" is used for a individual while "Native to" is used for a large group