TANCET 2014 DS Question 61: Percents

Directions

The question is followed by two statements labeled (1) and (2) in which certain data are given. You have to decide whether the data given in the statements are sufficient for answering the question. Using the data given in the problem plus your knowledge of mathematics and everyday facts, choose the answer as:

Choice 1 if statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
Choice 2 if statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
Choice 3 if both the statements (1) and (2) TOGETHER are sufficient, but NEITHER statement alone is sufficient.
Choice 4 if each statement ALONE is sufficient.
Choice 5 if statements (1) and (2) TOGETHER are not sufficient, and additional data is needed.

Question

Easy Data Sufficiency

If only people who paid the deposits attended the Management Seminar, how many people attended this year?

Statement 1: 70 people sent in deposits to attend the Management Seminar this year.
Statement 2: 60 percent of the people who sent deposits to attend the Management Seminar this year actually went.

Correct Answer Choice (3). Both statements are needed to answer the question.

Explanatory Answer - step by step

Question Statement (1) Alone Statement (2) Alone Statements Together Tabs

What do we know from the Question Stem?

Before evaluating the two statements, answer the following questions to gain clarity.

What kind of an answer will the question fetch?

The question is "how many people attended this year?"

The answer should be a number - giving the number of people who attended the seminar this year.

When is the data sufficient?

If we are able to come up with unique value for the number of people who attended the seminar this year, the data is sufficient.

If we are either not able to come up with a unique answer (i.e., if we get more than one answer) or if the data is not enough to find the number of people, the data is NOT sufficient.

What else is know from the question?

The question clearly states that "only people who paid the deposits attended the Management Seminar". So, we need not consider anyone outside the set of those who paid deposits.
Statement (1) ALONE

70 people sent in deposits to attend the Management Seminar this year.

The statement provides information about the number of people who sent in deposits this year. However, not all those who sent in deposits may have attended the seminar.

Without knowing whether all of them attended or only a fraction of those who sent the deposit attended, we will not be able to find the answer.

Statement (1) ALONE is NOT sufficient.

The moment we realize that statement (1) is NOT sufficient, we can eliminate choices 1 and 4.

We can narrow down our choices to 2, 3 and 5.
Statement (2) ALONE

60 percent of the people who sent deposits to attend the Management Seminar this year actually went.

Remember: When you are evaluating statement (2) ALONE, please do not recall information that you read in statement (1).

60 percent of the people who sent deposits attended.

If 1000 sent in their deposits, the answer to the question will be 600.

If 100 sent in their deposits, the answer to the question will be 60.

We are not getting a unique value for the number of people who attended the seminar from this staement.

Statement (2) ALONE is NOT sufficient.

We can eliminate choice 2.

The answer narrows down to 3 or 5.
Combine the statements

1. 70 people sent in deposits to attend the Management Seminar this year.

2. 60 percent of the people who sent deposits to attend the Management Seminar this year actually went.

Using the information in the two statements, we can deduce that 60% of 70 = 42 people attended the seminar.

Using the two statements, we could get a unique answer to the question

Hence, the correct answer is Choice 3. Both statements are needed to answer the question.