Each vote in a certain election went to one of two candidates, X or Y.

We already know how many how many men voted for X. to get the total votes of X we need 'how many women voted for X

St1: Does not tell how many women voted for X
St2: If 483 women is 60% of total women then total no. of women voters: 483/0.6. If we subtract 483 from this we will get no. of women who voted for X. SUFF
Ans: B

Here is a rip off each-of-people-voted-once-in-an-election-x-got-483-from-27128.html for practice

This is a copy of GMAT Prep question: each-person-on-a-committee-with-40-members-voted-for-exactly-129999.html

We can use the Double Matrix Method here to help us arrange our information. The Double Matrix can be used for most questions featuring a population in which each member has two characteristics associated with it.
Here, we have a population of voters, and the two characteristics are:
- male or female
- voted for X or voted for Y

So, we can set up out diagram as follows:


X got 483 from male voters, Y got 433 from female voters.
We can add that information as follows:


Target question: How many votes did X get?
Notice that the two blue boxes represent the males and females who voted for X.

So, our goal here is to find the sum of these two boxes.

Statement 1: X got votes from 50% of male voters
The two highlighted boxes represent the male voters. If 50% of them voted for X, then the other 50% voted for Y.



So, 483 of the males also voted for Y...


We can now see that we don't have enough information to find the sum of the values in the 2 blue boxes


As such, statement 1 is NOT SUFFICIENT


Statement 2: Y got votes from 60% of female voters
The two highlighted boxes represent the female voters.

Let's let F = the total number of female voters.
If 60% of the females voted for Y, then we can write 0.6F = 433
If we wanted to, we COULD solve this equation for F, at which point we COULD ALSO determine the number of females who voted for X.
Since we COULD determine the number of females who voted for X, then we COULD ALSO find the total number of people who voted for X

Since we could easily answer the target question with certainty, statement 2 is SUFFICIENT

Answer: B

To learn more about the Double Matrix Method, watch this video:



Here's a practice question:

We are given that Candidate X received 624 votes cast by men and candidate Y received 483 votes cast by women. We need to determine the number of votes X received.

Statement One Alone:

Candidate X received 50% cast by men.

We can create the equation:

624 = 0.5m

1,248 = m

So we see that the total votes cast by men was 1,248. However, since we don’t know the number of votes he received from women, we cannot determine the total number of votes X received.

Statement Two Alone:

Candidate Y received 60% cast by women.

We can create the equation:

483 = 0.6w

805 = w

So we see that the total votes cast by women was 805, so we see that X received 805 - 463 = 342 votes from women. Therefore, X received a total of 624 + 342 = 966 votes.

Answer: B

(1) This means 624 votes cast by men voted for women. Y = 483 + 624. However we can't determine the votes Candidate X received.

(2) If Candidate Y received 60% of votes cast by women, then 40% of women voted for for Candidate X. We can determine the total votes Candidate X received. SUFFICIENT.

Answer is B.

Hi JeffTargetTestPrep Bunuel

Why cannot we interpret statement one as follows:

Candidate X received 50% cast by men = Of all the votes that were cast to Candidate X, 50% of them were by men. So with this interpretation, we can say that men and women cast an equal number of votes to Candidate X. Hence the total number of votes to X = 624+624 = 1248.

Hence, statement 1 alone is sufficient.

Could you please let me know where am I getting wrong here?

Regards.

Whenever % are given, we need to be very careful with % out of what or what is the total.
So when you read statement 1, it says X received 50% of what ? What = votes cast by men

Candidate X received 50% cast by men

shouldn't it be 805- 483= 322. therefore, 624+ 322 = 946

Statement 1: X got votes from 50% of male voters
The two highlighted boxes represent the male voters. If 50% of them voted for X, then the other 50% voted for Y.

Here why are we not considering the statements being framed in exactly the same format as mentioned in the question?
Question says "Candidate X received 624 votes cast by men"
We considered this as 624 of the totals votes received by X were by men

Now
The given statement 1 says "Candidate X received 50% cast by men"
Doesn't that mean that 50% of the total votes received by candidate X were by men?

Considering this shouldn't the answer be A?

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