Ms. Robbins

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Ms. Robbins

by rsarashi » Sat Feb 11, 2017 9:54 am
In a recent election, Ms. Robbins received 8,000 votes cast by independent voters, that is, voters not registered with a specific political party. She also received 10 percent of the votes cast by those voters registered with a political party. If N is the total number of votes cast in the election and 40 percent of the votes cast were cast by independent voters, which of the following represents the number of votes that Ms. Robbins received?

(A) 0.06N + 3,200
(B) 0.1N + 7,200
(C) 0.4N + 7,200
(D) 0.1N + 8,000
(E) 0.06N + 8,000

OAE

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by [email protected] » Sat Feb 11, 2017 11:04 am
Hi rsarashi,

This question can actually be answered with just a little logic (no real calculations are required).

From the first sentence, we know that Ms. Robbins received 8,000 votes; and from the second sentence, we know she received 10% of the votes from voters registered with a political party. We're told that N is the TOTAL number of votes cast. Since the 10% that were mentioned was NOT 10% of the total votes, the remaining votes that Ms. Robbins received CANNOT be described as .1N (it has to be something LESS than .1N). There's only one answer that matches.

Final Answer: E

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by Brent@GMATPrepNow » Sun Feb 12, 2017 10:03 am
rsarashi wrote:In a recent election, Ms. Robbins received 8,000 votes cast by independent voters, that is, voters not registered with a specific political party. She also received 10 percent of the votes cast by those voters registered with a political party. If N is the total number of votes cast in the election and 40 percent of the votes cast were cast by independent voters, which of the following represents the number of votes that Ms. Robbins received?

(A) 0.06N + 3,200
(B) 0.1N + 7,200
(C) 0.4N + 7,200
(D) 0.1N + 8,000
(E) 0.06N + 8,000

OAE
N is the total number of votes cast in the election and 40 percent of the votes cast were cast by independent voters
If 40% of the total voters are independent, then the remaining 60% of the total voters are NOT independent.
In other words, 60% of the total voters (N) are registered voters.
So, the number of registered voters = 0.6N

Ms. Robbins received received 10% of the votes from registered voters
10% of the registered voters = 10% of 0.6N = (0.1)(0.6N) = 0.06N

Ms. Robbins received 8,000 votes cast by independent voters

TOTAL number of votes that Ms. Robbins received = (votes from registered voters) + (votes from independent voters)
= 0.06N + 8,000
= E

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by Jeff@TargetTestPrep » Wed Feb 15, 2017 3:10 pm
rsarashi wrote:In a recent election, Ms. Robbins received 8,000 votes cast by independent voters, that is, voters not registered with a specific political party. She also received 10 percent of the votes cast by those voters registered with a political party. If N is the total number of votes cast in the election and 40 percent of the votes cast were cast by independent voters, which of the following represents the number of votes that Ms. Robbins received?

(A) 0.06N + 3,200
(B) 0.1N + 7,200
(C) 0.4N + 7,200
(D) 0.1N + 8,000
(E) 0.06N + 8,000
We are given that Ms. Robbins received 8,000 votes cast by independent voters and 10% of the votes cast by those who are affiliated with a party.

Since N is the total number of votes and 40% of the votes were cast by independent voters, 60% of the votes were cast by voters who are affiliated with a party .

Since Ms. Robbins received 10% of the votes cast by those who are affiliated with a party, she received (0.1)(0.6)N = 0.06N of the votes from voters who are affiliated with a party. Since she also received 8,000 votes from independent voters, she received 0.06N + 8,000 total votes.

Answer: E

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by Matt@VeritasPrep » Wed Feb 15, 2017 5:43 pm
Independent voters = .4n

Party voters = .6n

Ms. Robbins got 8000 from the indies and 10% of the .6n party voters, so 8000 + .1*.6n, or E.

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by Matt@VeritasPrep » Wed Feb 15, 2017 5:44 pm
Another timesaver here is noticing that Ms. Robbins got 8000 + (some variable), so the answer must be D or E. Since 10% of the entire population is too much (she only got 10% of a FRACTION of the population), D is out, so it's E by default.

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by Matt@VeritasPrep » Wed Feb 15, 2017 5:45 pm
One last approach would be plugging in.

Suppose N = 100,000.

That means we've got 40,000 indies and 60,000 registered voters.

Ms. Robbins got 8,000 indies and 10% of 60,000, or 6,000 registered voters, so our target answer is 8,000 + 6,000.

Plugging N = 100,000 into the answers, only E fits, so we're done.