Bunuel
On Monday, Nicole spent $780 on fifty-two collector’s comic books. She then returned to the comic book store on Tuesday and purchased eight more comics. Was the mean price she paid per book more than $20?(1) Each of the comic books she purchased on Tuesday cost more than $30.(2) Each of the comic books she purchased on Tuesday cost less than $40.
Given that, on Monday, we have 52 books amounting to a total of $780. And then we have 8 more books on Tuesday.
Find whether the average price of all the books is less than 20
Stmt 1 says that those 8 books cost more than 30.
This is an open ended statement, we have not limit on the prices of the 8 books. The cost per book could be $31 or $100 or even more.
If the cost per book is $31, then 8 books would cost, $248. Total average would be (780+248)/60 which is equal to $17.13.
If the cost per book is $100, then 8 books would cost, $800. Total average would be (780+800)/60 which is equal to $26.33.
Stmt 1 is not sufficient.
Stmt 2 limits us saying that the price per book is less than $40, that means the maximum price the books can be of is $39.9.
If the price per book is $39.9, then 8 books would cost, $319.20. Total average would be (780+319.20)/60 which is equal to $18.32.
Which means the average cost is less than $20 no matter what.
Hence, statement 2 is sufficient.
Answer B.