65 yrs ols

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by Zipper » Sun Jan 25, 2009 11:22 pm
1) no info about employment.

2) if there are 5 man and 10 women (minimum possible)

2 working from 15 it's above 10% of the total.

So B is sufficient.

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by gaggleofgirls » Mon Jan 26, 2009 7:07 pm
I am sorry, Zipper, I don't understand why 5 men and 10 women are the minimum possible. Can you further explain?

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by Zipper » Mon Jan 26, 2009 8:32 pm
Sure,

we know that 20% of the men over 65 are still working.

we can't have 4 men coz 20% of 4 men would be 4/5, not a complete person. You can't have 7 men for instance coz the working men would be 1 and 2/5 men. it can be 10, 15 20 and so on, has to be a multiple of 5.

NOTE that you don't need the number of people to know the percentage. I went with 5 coz it was the first number that worked and you could calculate if the percentage of the whole group of people will be over 10%.

The same goes for women.

We don't know what percent of the population over 65 are men or women but since neither men or women are less than 10% hence we don't need the number of people/percents(men, women) in order to be sure that the group has more than 10% working.

I hope it's clearer now.

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by sanju09 » Tue Jan 27, 2009 6:12 am
Zipper wrote:Sure,

we know that 20% of the men over 65 are still working.

we can't have 4 men coz 20% of 4 men would be 4/5, not a complete person. You can't have 7 men for instance coz the working men would be 1 and 2/5 men. it can be 10, 15 20 and so on, has to be a multiple of 5.

NOTE that you don't need the number of people to know the percentage. I went with 5 coz it was the first number that worked and you could calculate if the percentage of the whole group of people will be over 10%.

The same goes for women.

We don't know what percent of the population over 65 are men or women but since neither men or women are less than 10% hence we don't need the number of people/percents(men, women) in order to be sure that the group has more than 10% working.

I hope it's clearer now.
IMO B

and my explanation is not a single word different from yours. What should I be writing in such cases, Zipper? B-)
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by piyush_nitt » Tue Jan 27, 2009 10:19 pm
sanju09 wrote:
Zipper wrote:Sure,

we know that 20% of the men over 65 are still working.

we can't have 4 men coz 20% of 4 men would be 4/5, not a complete person. You can't have 7 men for instance coz the working men would be 1 and 2/5 men. it can be 10, 15 20 and so on, has to be a multiple of 5.

NOTE that you don't need the number of people to know the percentage. I went with 5 coz it was the first number that worked and you could calculate if the percentage of the whole group of people will be over 10%.

The same goes for women.

We don't know what percent of the population over 65 are men or women but since neither men or women are less than 10% hence we don't need the number of people/percents(men, women) in order to be sure that the group has more than 10% working.

I hope it's clearer now.
IMO B

and my explanation is not a single word different from yours. What should I be writing in such cases, Zipper? B-)
Thanks for all help guys!

OA is indeed B

But I need a clarification here

As per my understanding we need to answer the Question that "what percentage of population comprises of 65 yr old working men or women"?

1. gives you total population : say if total population is 100% then 11.3%among them are 65 yrs and old.

2. gives a %age of 65 yrs old working : so 20% of 65 yrs old men or 10 % of of 65 yrs old women

As per 2 we cannot make out what is the percentage of 65 yrs old in the entire population and that information is provided by 1.

Using both we can find out the exactly what percentage of entire population 65 yrs old working men or women comprises.

there fore correct answer should be C.

Please correct ME!

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by sanju09 » Wed Jan 28, 2009 4:14 am
piyush_nitt wrote:
sanju09 wrote:
Zipper wrote:Sure,

we know that 20% of the men over 65 are still working.

we can't have 4 men coz 20% of 4 men would be 4/5, not a complete person. You can't have 7 men for instance coz the working men would be 1 and 2/5 men. it can be 10, 15 20 and so on, has to be a multiple of 5.

NOTE that you don't need the number of people to know the percentage. I went with 5 coz it was the first number that worked and you could calculate if the percentage of the whole group of people will be over 10%.

The same goes for women.

We don't know what percent of the population over 65 are men or women but since neither men or women are less than 10% hence we don't need the number of people/percents(men, women) in order to be sure that the group has more than 10% working.

I hope it's clearer now.
IMO B

and my explanation is not a single word different from yours. What should I be writing in such cases, Zipper? B-)
Thanks for all help guys!

OA is indeed B

But I need a clarification here

As per my understanding we need to answer the Question that "what percentage of population comprises of 65 yr old working men or women"?

1. gives you total population : say if total population is 100% then 11.3%among them are 65 yrs and old.

2. gives a %age of 65 yrs old working : so 20% of 65 yrs old men or 10 % of of 65 yrs old women

As per 2 we cannot make out what is the percentage of 65 yrs old in the entire population and that information is provided by 1.

Using both we can find out the exactly what percentage of entire population 65 yrs old working men or women comprises.

there fore correct answer should be C.

Please correct ME!
It is needless to mention again that st 1 is not sufficient to answer the question. Now, why B? And why not C? So see:

Read the question stem, it asks whether or not the percent of working persons of the said category, is atleast 10; and st 2 reads that 20% of men of the said category, and 10% of women of the said category are working. When we come down to decide the minimum possible number of working men or women, it is always 1 in each case. If 20% of men of the said category is 1 man, then total number of men of said category will be 5; and if 10% of women of the said category is 1 woman, then total number of women of said category will be 10. This means that a feasible sample of (5 m + 10 w) 15 persons will definitely contain (1 m + 1 w) 2 persons as working; and (2/15)*100% > 10%.

This way, we are always able to answer it using statement 2 alone. Hence B. We do not require st 1 be mixed, hence not C.

I hope doubts are cleared now, isn't it?
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E

by sdjomou » Wed Jan 28, 2009 4:38 am
Both statement are not sufficient the answer is E

let's say the country X has 10,000 inhabitants. 10% being 65 years and older.... means we have 1,000 people who are supposed to be 65 years and older into employment. That is what we want to verify.

Statement 1
from the 10,000 we have 11.3% older that means 1,130 are 65 years and older, we want to know if from those 1,130 old people, 1,000 are into employment


Using statement 2
we cannot go further as we don't know which part of the 1,130 are women and which part are men.... so we cannot deduce 10% of old women into employment when we don't know the total elderly women population.


so both statement are not sufficient to answer the question.

If we knew for example that from the 1,130 people, 500 were men and 630 were women we could have calculate which part is employed: 10% of 630 is 63 and 20% of 500 is 100 and see if it equals 1,000 or not. 163 is less than 1000
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by sdjomou » Wed Jan 28, 2009 4:43 am
SORRY I HAVE TO CORRECT MYSELF

Statement 1 and 2 together are sufficient to answer the question but each statement alone is not sufficient.

If we have total population 10,000
10% older employed? means 1,000 older people employed?

Using statement 1
Total elderly population 11.3% equals 1,130 old people
10% women and 20% men into employment just means that at least 30% of the total elderly population are into employment....
so 30% of 1,130 old people are into employment, this is definitely less than 1,000
so using both statement in combination you can answer the question....


YEAH
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Re: 65 yrs ols

by kashi125 » Wed Jan 28, 2009 1:06 pm
B is the right answer

Note that we do NOT need to know the EXACT number of employed people over 65. We just need to know whether it is at least 10%.

Also note that the question does not ask whether 10% of the ENTIRE population is employed. Only 10% of those 65 or older...

Since the second statement already tells us of the population 65 years old or older , we know for sure that 20% (men employed over 65) + 10% (women employed over 65) would be at least 10% (total employed over 65)