At a certain organization, the number of male members went up by 12% in the year 2001 from the year 2000, and the number of females members went down by 6% in the same time period. If the total membership at the organization went up by 1.2% from the year 2000 to 2001, what was the ratio of male members to female members in the year 2000?
a.1:2
b.1:3
c.2:3
d.3:2
e.2:1
The OA is the option C.
This ratio questions are difficult. Could anyone give me a detailed explanation, please? Thanks in advance.
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At a certain organisation, the number of
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This is a MIXTURE problem.M7MBA wrote:At a certain organization, the number of male members went up by 12% in the year 2001 from the year 2000, and the number of females members went down by 6% in the same time period. If the total membership at the organization went up by 1.2% from the year 2000 to 2001, what was the ratio of male members to female members in the year 2000?
a.1:2
b.1:3
c.2:3
d.3:2
e.2:1
Percent change for men = +12%.
Percent change for women = -6%.
Percent change for the MIXTURE of men and women = +1.2%.
The following approach is called ALLIGATION -- a very efficient way to handle MIXTURE PROBLEMS.
Let M = men and W = women.
Step 1: Plot the 3 percent changes on a number line, with the percent changes for M and W on the ends and the percent change for the mixture in the middle.
M +12%..........................+1.2%.......................-6% W
--
Step 2: Calculate the distances between the percentages.
M +12%.......10.8.........+1.2%........7.2.........-6% W
Step 3: Determine the ratio in the mixture.
The ratio of M to W is equal to the RECIPROCAL of the distances in red.
M:W = 7.2 : 10.8 = 72:108 = 2:3.
The correct answer is C.
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We can create the equation:M7MBA wrote:At a certain organization, the number of male members went up by 12% in the year 2001 from the year 2000, and the number of females members went down by 6% in the same time period. If the total membership at the organization went up by 1.2% from the year 2000 to 2001, what was the ratio of male members to female members in the year 2000?
a.1:2
b.1:3
c.2:3
d.3:2
e.2:1
1.12m + 0.94f = 1.012(m + f)
112m + 94f = 101.2m + 101.2f
10.8m = 7.2f
m/f = 7.2/10.8 = 72/108 = 2/3
Answer: C
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Hi All,
We're told that at a certain organization, the number of male members went up by 12% in the year 2001 from the year 2000, the number of females members went down by 6% in the same time period and the total membership at the organization went up by 1.2% from the year 2000 to 2001. We're asked for the ratio of male members to female members in the year 2000. This question can be solved with a mix of TESTing THE ANSWERS and TESTing VALUES.
To start, since 6% is exactly half of 12%, we know that IF there were exactly twice the number of women as men, then the increase and decrease in the total size of the group would 'cancel out.' You can prove this by TESTing VALUES.
IF....
There were 100 men and 200 women...
a 12% increase in the men would be (.12)(100) = 12 men....
a 6% decrease in the women would be (.06)(200) = 12 women...
so the total would stay 300.
The prompt tells us that the total membership increased by 1.2% though, so the ratio of men to women won't be 1:2 exactly (although it should be pretty close; the number of men has to be a little higher, so the ratio would have to be LESS than 1/2). There's only one answer that matches that logic: Answer C (2:3). We can prove that it's the answer...
IF....
There were 200 men and 300 women...
a 12% increase in the men would be (.12)(200) = 24 men....
a 6% decrease in the women would be (.06)(300) = 18 women...
so the total would increase by 6 people (from 500 to 506). That increase is 6/500 = 12/1000 = 1.2%
This is an exact match for what we were told, so this must be the answer.
Final Answer: C
GMAT assassins aren't born, they're made,
Rich
We're told that at a certain organization, the number of male members went up by 12% in the year 2001 from the year 2000, the number of females members went down by 6% in the same time period and the total membership at the organization went up by 1.2% from the year 2000 to 2001. We're asked for the ratio of male members to female members in the year 2000. This question can be solved with a mix of TESTing THE ANSWERS and TESTing VALUES.
To start, since 6% is exactly half of 12%, we know that IF there were exactly twice the number of women as men, then the increase and decrease in the total size of the group would 'cancel out.' You can prove this by TESTing VALUES.
IF....
There were 100 men and 200 women...
a 12% increase in the men would be (.12)(100) = 12 men....
a 6% decrease in the women would be (.06)(200) = 12 women...
so the total would stay 300.
The prompt tells us that the total membership increased by 1.2% though, so the ratio of men to women won't be 1:2 exactly (although it should be pretty close; the number of men has to be a little higher, so the ratio would have to be LESS than 1/2). There's only one answer that matches that logic: Answer C (2:3). We can prove that it's the answer...
IF....
There were 200 men and 300 women...
a 12% increase in the men would be (.12)(200) = 24 men....
a 6% decrease in the women would be (.06)(300) = 18 women...
so the total would increase by 6 people (from 500 to 506). That increase is 6/500 = 12/1000 = 1.2%
This is an exact match for what we were told, so this must be the answer.
Final Answer: C
GMAT assassins aren't born, they're made,
Rich
