A book store-bought copies of a new book by a popular author, in anticipation of robust sales. The store-bought 400 copies from their supplier, each copy at wholesale price \(W.\) The store sold the first 150 copies in the first week at 80% more than \(W,\) and then over the next month, sold a 100 more at 20% more than \(W.\) Finally, to clear shelf space, the store sold the remaining copies to a bargain retailer at 40% less than \(W.\) What was the bookstore’s net percent profit or loss on the entire lot of 400 books?

(A) 30% loss

(B) 10% loss

(C) 10% profit

(D) 20% profit

(E) 60% profit

[spoiler]OA=D[/spoiler]

Source: Magoosh

## A book store-bought copies of a new book by a popular author, in anticipation of robust sales. The store-bought 400 copi

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M7MBA wrote: ↑Sat Aug 01, 2020 6:06 amA book store-bought copies of a new book by a popular author, in anticipation of robust sales. The store-bought 400 copies from their supplier, each copy at wholesale price \(W.\) The store sold the first 150 copies in the first week at 80% more than \(W,\) and then over the next month, sold a 100 more at 20% more than \(W.\) Finally, to clear shelf space, the store sold the remaining copies to a bargain retailer at 40% less than \(W.\) What was the bookstore’s net percent profit or loss on the entire lot of 400 books?

(A) 30% loss

(B) 10% loss

(C) 10% profit

(D) 20% profit

(E) 60% profit

[spoiler]OA=D[/spoiler]

Source: Magoosh

**STRATEGY: Since the answer choices aren't in terms of the variable W, let's make matters easier for ourselves by assigning a convenient number to W. have**

Let's say

**W = $100**

*The store bought 400 copies from their supplier, each copy at wholesale price W ($100)*So, the total amount spent by the store = (400)(

**$100**) =

**$40,000**

*The store sold the first 150 copies in the first week at 80% more than W.... (= 80% more than $100 = $180)*So, the revenue for the first 150 copies = (150)($180) =

**$27,000**

*..., and then over the next month, sold a 100 more at 20% more than W (= 20% more than $100 = $120)*So, the revenue for the next 100 copies = (100)($120) =

**$12,000**

*Finally, to clear shelf space, the store sold the remaining copies to a bargain retailer at 40% less than W (= 40% less than $100 = $60)*So, the revenue for the last remaining 150 copies = (150)($60) =

**$9,000**

*What was the bookstore’s net percent profit or loss on the entire lot of 400 books?*The store spent a total of

**$40,000**purchasing the books.

The store's total revenue =

**$27,000**+

**$12,000**+

**$9,000**=

**$48,000**

So, the store's profit =

**$48,000**-

**$40,000**=

**$8,000**

So, the net percent profit =

**$8,000**/

**$40,000**

**= 8/40 = 1/5 = 20%**

Answer: D