DS - eqn

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DS - eqn

by karthikpandian19 » Tue Jul 03, 2012 1:02 am
How many people voted for Initiative Q?

Of the total number of votes for Initiative Q, 20 percent came from people aged 65 or over, and 16,000 came from people aged over age 75.

Of the total number of votes for Initiative Q, 1.5 million came from people under the age of 65, and 15% came from people between the ages of 18 and 21.
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by Anurag@Gurome » Tue Jul 03, 2012 1:08 am
karthikpandian19 wrote:How many people voted for Initiative Q?

Of the total number of votes for Initiative Q, 20 percent came from people aged 65 or over, and 16,000 came from people aged over age 75.

Of the total number of votes for Initiative Q, 1.5 million came from people under the age of 65, and 15% came from people between the ages of 18 and 21.
Statement 1: We don't have any idea about the number of votes that came from people under the age of 65.

Not sufficient

Statement 2: We don't have any idea about the number of votes that came from people aged 65 or over.

Not sufficient

1 & 2 Together: Now we know that of the total number of votes for Initiative Q, (100 - 20) = 80% vote came from people under the age of 65, which is equal to 1.5 million. Hence, we can find the total number of people who voted for Initiative Q.

Sufficient

The correct answer is C.
Last edited by Anurag@Gurome on Tue Jul 03, 2012 4:06 am, edited 1 time in total.
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by karthikpandian19 » Tue Jul 03, 2012 4:04 am
Hi Anurag,

I think you made a typo at the last part when mentioning the answer. Can you edit that to C
Anurag@Gurome wrote:
karthikpandian19 wrote:How many people voted for Initiative Q?

Of the total number of votes for Initiative Q, 20 percent came from people aged 65 or over, and 16,000 came from people aged over age 75.

Of the total number of votes for Initiative Q, 1.5 million came from people under the age of 65, and 15% came from people between the ages of 18 and 21.
Statement 1: We don't have any idea about the number of votes that came from people under the age of 65.

Not sufficient

Statement 2: We don't have any idea about the number of votes that came from people aged 65 or over.

Not sufficient

1 & 2 Together: Now we know that of the total number of votes for Initiative Q, (100 - 20) = 80% vote came from people under the age of 65, which is equal to 1.5 million. Hence, we can find the total number of people who voted for Initiative Q.

Sufficient

The correct answer is E.
Regards,
Karthik
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by karthikpandian19 » Tue Jul 03, 2012 4:05 am
OA is C


We will represent the total votes for Initiative Q with the letter x. The question asks us if we have enough information to determine the value of x.

Statement 1 tells us that 20 percent of the votes for Initiative Q came from people aged 65 or over, and that 16,000 were over age 75. Twenty percent can be written as 0.2, so 20 percent of x can be expressed as 0.2x. However, we do not know the actual number of people 65 or over who voted for Initiative Q, so we do not know the value of 0.2x, and therefore cannot solve for x. The fact that 16,000 people were over age 75 has no bearing on the problem-it is just "filler" information and can be ignored. Statement 1 alone is NOT sufficient to answer the question. Eliminate answer choices A and D. The correct answer choice is B, C, or E.

Statement 2 tells us that 1.5 million people under the age of 65 voted for Initiative Q, and that 15% were between the ages of 18 and 21. Again, since we have no other information about people between the ages of 18 and 21, this information is irrelevant. However, we do not know the number of people over the age of 65 who voted for the initiative, so this information does not allow us to solve for x either. Statement 2 alone is also NOT sufficient to answer the question. Eliminate answer choice B. The correct answer choice is either C or E.

Both statements together tell us that 0.2x people 65 or over voted for the initiative and that 1.5 million people under the age of 65 voted for the initiative. Since x is the sum of these two numbers, we can write the following equation: 0.2x + 1,500,000 = x. We can solve this equation for a unique value of x, and so both statements together are sufficient to answer the question.
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Karthik
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by Anurag@Gurome » Tue Jul 03, 2012 4:09 am
karthikpandian19 wrote:Hi Anurag,

I think you made a typo at the last part when mentioning the answer. Can you edit that to C
Thanks for pointing it out.
I've edited the reply.
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