A shelf contains only books of poetry, short stories, and non-fiction.

Question

A shelf contains only books of poetry, short stories, and non-fiction. If Jana draws a book randomly off the shelf, what is the probability that the book will be non-fiction?

(1) There are 15 books on the shelf.
(2) There are 4 books of poetry and 5 books of short stories on the shelf.

Senthil1981 · Answer

A shelf contains only books of poetry, short stories, and non-fiction. If Jana draws a book randomly off the shelf, what is the probability that the book will be non-fiction?

Question is Non-fiction / Total number of books

(1) There are 15 books on the shelf.
 This only gives the denominator , So eliminate A and D

(2) There are 4 books of poetry and 5 books of short stories on the shelf. 
 This does not give info about Non Fiction, so eliminate B 
1) + 2) gives info about Numerate and Denominator, So C ) Both statements 1 and 2 together are sufficient to answer the question but neither statement is sufficient alone.

Manonamission · Answer

(1) There are 15 books on the shelf. 
(2) There are 4 books of poetry and 5 books of short stories on the shelf.

Probability of an Event = Number of Favorable Outcomes / Total Number of Possible Outcomes
 
Using (1) , Number of Favorable Outcomes = 0
 Total Number of Possible Outcomes = 15 => NS

Using (2) , Number of Favorable Outcomes = 6
 Total Number of Possible Outcomes = 0 => NS

Using both , Probability = 6/15 = 2/5 .
Hence , option C

duahsolo · Answer

(1) There are 15 books on the shelf. =====> no information about # of non-fiction books on the shelves. Not sufficient

(2) There are 4 books of poetry and 5 books of short stories on the shelf ======> No information about the total # of books on the shelves. Not sufficient

Together (1) + (2)

We know that there are ONLY books of poetry, short stories & non-fictions on the shelves, so we can conclude that the 15 books on the shelves must be of only those books. so total books = 15

# of non-fiction books = 15 - other books = 15 - (4+5) = 6

Probability of non-fiction being drawn (i.e., # of non-fiction books/total # of books) can be calculated (= 6/15). Sufficient.

Answer: C

PulkitMudgal · Answer

I can not see the options for the question

Bunuel · Answer

Hi,

This is a data sufficiency question. Options for DS questions are always the same and usually omitted on the site.

The data sufficiency problem consists of a question and 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 statements, plus your knowledge of mathematics and everyday facts (such as the number of days in July or the meaning of the word counterclockwise), you must indicate whether—

A. Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient to answer the question asked.
B. Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient to answer the question asked.
C. BOTH statements (1) and (2) TOGETHER are sufficient to answer the question asked, but NEITHER statement ALONE is sufficient to answer the question asked.
D. EACH statement ALONE is sufficient to answer the question asked.
E. Statements (1) and (2) TOGETHER are NOT sufficient to answer the question asked, and additional data specific to the problem are needed.

I suggest you to go through the following post  ALL YOU NEED FOR QUANT .

Hope this helps.

PulkitMudgal · Answer

this definitely did

A shelf contains only books of poetry, short stories, and non-fiction.

Prep Toolkit

Top 5 GMAT Debrief Videos

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards

GMAT Data Sufficiency (DS) Questions

A shelf contains only books of poetry, short stories, and non-fiction.

Prep Toolkit

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards