A certain bookstore sold 1/2 of the books in its stock. Then, after an

OA is D. As eith statement is sufficient alone.
Statement 1 says. 20 books are left after advertising that means it stating the unsold 1/3 part of the total books present in the book shop. Which is 20*3 = 60 so 40 books are sold. ( Sufficient)

Statement 2: 30 books sold before campaign which were half of the total books. That means 60 were present in the book store and after campaign 1/3 of remaining books are sold. Which comes to 30/3 = 10 so total books sold is 40 (sufficient)
So D is OA because either of the statement is sufficient.

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Solution

Step 1: Analyse Question Stem

• Let the total number of books be x.

o Books sold before campaign = \(\frac{x}{2}\)
o Books left in stock before campaign = \(\frac{x}{2}\)
• Books sold after campaign = \(\frac{x}{2} *\frac{1}{3}= \frac{x}{6}\)

o Total books sold = \(\frac{x}{2} + \frac{x}{6} = \frac{4x}{6}=\frac{2x}{3}\)
o Books left after campaign = \(x – \frac{2x}{3} = \frac{x}{3}\)

We need to find the total number of books sold.

• \(\frac{2x}{3}\), we need the value of x.

Step 2: Analyse Statements Independently (And eliminate options) – AD/BCE

Statement 1: After the advertising campaign, the bookstore left with 20 unsold books.

• \(\frac{x}{3} = 60\)

o We can find the value of x with this information.

Hence, statement 1 is sufficient, we can eliminate answer options B, C, and E.
Statement 2: Before the advertising campaign, the bookstore had sold 30 books.

• \(\frac{x}{2} = 30\)

o We can find the value of x with this information.

Hence, statement 2 is also sufficient, the correct answer is Option D.

A certain bookstore sold 1/2 of the books in its stock. Then, after an aggressive advertising campaign, the bookstore sold 1/3 of the remaining books in its stock. How many of the books did the bookstore sell from its stock?

Let Total number of books = B
Total Books sold = \(\frac{B}{2} + \frac{1}{3} * \frac{B}{2} = \frac{2}{3}B\)

(1) After the advertising campaign, the bookstore was left with 20 unsold books.
Unsold Books = \(B - \frac{2}{3}*B\) = 20
B = 60

SUFFICIENT.

(2) Before the advertising campaign, the bookstore had sold 30 books.
\(\frac{B}{2}\) = 30

B = 60

SUFFICIENT.

Answer D.

A certain bookstore sold 1/2 of the books in its stock. Then, after an aggressive advertising campaign, the bookstore sold 1/3 of the remaining books in its stock. How many of the books did the bookstore sell from its stock?

(1) After the advertising campaign, the bookstore was left with 20 unsold books.
(2) Before the advertising campaign, the bookstore had sold 30 books.

Total books be x.
before advertising: books sold =\(\frac{1*x}{2}\)

after advertising: books sold = \(\frac{1}{3}*\frac{1*x}{2}\) = \(\frac{1*x}{6}\)

statement 1: books left = \(\frac{1*x}{3}=20\); x = 60
books sold = 40; sufficient

statement 2: 30 = \(\frac{1*x}{2}\); x =60
books sold = 30 + 10; sufficient.

Ans: D

A certain bookstore sold 1/2 of the books in its stock. Then, after an aggressive advertising campaign, the bookstore sold 1/3 of the remaining books in its stock. How many of the books did the bookstore sell from its stock?

(1) After the advertising campaign, the bookstore was left with 20 unsold books.
(2) Before the advertising campaign, the bookstore had sold 30 books.

Before the campaign, the store sold 1/2 of it's books. After the campaign it sold 1/2*1/3= 1/6 of it's book. So, the remaining portion of books is (1/2*2/3)= 1/3. If the value of any of this fraction can be known, we can determine total number of books sold.

1) So, the 1/3 of the books are 20. We can find the total books as and the number of books sold as 40 from this information. sufficient.

2) 1/2 of the books are 30. Total number of books are 60. Sold (60*2/3) =40. sufficient.

D is the answer.

We are informed that the bookstore sold half of the books in stocks, implying the remaining stock is half. Then the bookstore managed to sell 1/3 of the remaining books after an advertisement campaign, implying the fraction of books left after the advertisement sales is 1/2 - 1/3*1/2 = 1/3. We are to determine the number of books sold by the bookstore.

When we know the number of books left, we can work backward to get the total number of books and multiply by 2/3. In addition, when we know the number of books sold within the advertisement campaign and the number of books sold before the advertisement campaign, we can determine the total number of books and multiply by 2/3 to get the number of books sold.

(1) After the advertising campaign, the bookstore was left with 20 unsold books.
Sufficient. 1x/3=20 hence x=60. Number of books sold = 2*60/3 = 40.

(2) Before the advertising campaign, the bookstore had sold 30 books.
Sufficient. x/2=30 hence x=60. Number of books sold = 2*60/3 = 40.

the answer is D.

Total books sold= 5/6 of the books in stock
Total books left= 1/6 of the books in stock


(1) After the advertising campaign, the bookstore was left with 20 unsold books.....that's 1/6 of total books..from which we can calculate the books did the bookstore sell from its stock..... SUFFICIENT

(2) Before the advertising campaign, the bookstore had sold 30 books....From this we can calculatethe books did the bookstore sell from its stock.... SUFFICIENT

OA:D

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A certain bookstore sold 1/2 of the books in its stock. Then, after an aggressive advertising campaign, the bookstore sold 1/3 of the remaining books in its stock. How many of the books did the bookstore sell from its stock?

(1) After the advertising campaign, the bookstore was left with 20 unsold books.
(2) Before the advertising campaign, the bookstore had sold 30 books.
Solution:
Let, the total stocks = x
Before advertisement, The bookstore sold = x/2
After aggressive advertisement, The bookstore sold = 1/3(x/2) = x/6
Total sold = x/2 + x/6 = 2x/3. Therefore, unsold number of books = x/3

From statement (1),
x/3 = 20
X = 60, Hence, Sufficient.

From statement (2),
x/2 = 30
x = 60, Hence Sufficient.

Answer: C

Let’s say that the number of books in the bookstore is x
—> \(\frac{1}{2}\)x was sold
After the agressive advertising campaign, \(\frac{1}{3}\) of the remaining was sold —> \((1/3)(x—1/2x) =( \frac{1}{6})x\)

In total, \((1/2)x + (1/6)x = (2/3)x\) books were sold.
—>\(( \frac{2}{3})x\) —???

(Statement1): \((1/3)x = 20\)
\(x = 60\)
—>\(( 2/3)x = 40\)
Sufficient

(Statement2): \((1/2)x = 30\)
\(x= 60\)
—>\(( 2/3)x = 40\)
Sufficient

The answer is D

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A certain bookstore sold 1/2 of the books in its stock. Then, after an aggressive advertising campaign, the bookstore sold 1/3 of the remaining books in its stock. How many of the books did the bookstore sell from its stock?

(1) After the advertising campaign, the bookstore was left with 20 unsold books.
(2) Before the advertising campaign, the bookstore had sold 30 books.

1/2 of the books were stored before advertising and the remaining 1/3 of the 1/2 ie: 1/6th was sold after advertisement

Statement A:

remaining after unsold books were 5/6 were 20 5x/6=20
Therefore X= 4X20/5= 24

Total 48 books in store and sold 28 books
statement 1 is sufficient

Statement 2: As the half of the books is given we can determine the other half

Statement 2 is sufficient

IMO D

Lets say there were a total of x number of books in the stock.
1. After selling 1/2 of the books, stock = x/2
2. After aggressive marketing, store sold x/6 books.

We need to determine the value of x/2 + x/6 i.e. if We find the value of x, we can get the required answer.

Statement 1 - x/2 - x/6 = 20 From this we can find the value of x. Thus sufficient.

Statement 2 - x/2 = 30 From this we can find the value of x. Thus sufficient.