Data Sufficiency

We know that Store S sold 90 copies in 7 days and it sold same number of copies for 5 days.

Also we know that greatest number of copies were sold on Saturday and second greatest on Friday.
So for rest of the days of the week except Friday and Saturday, store S sold the same number of copies.

From Statement(1), 8 copies were sold on Thursday.
So the following can be inferred from the above statement:
(1) Highest sales was on Saturday
(2) Second highest was on Friday
(3) For each of the rest of 5 days of the week, 8 copies were sold.

Thus total copies sold on Friday and Saturday = 90- (5 * 8) = 50
But we are not sure whether more than 11 was sold on Friday or not.
For eg the sales might be 10 on Friday and 40 on Saturday (or) 15 on Friday and 35 on Saturday. No information given. Hence insufficient. BCE

From Statement(2), 38 copies was the maximum sold in store S. No information abt the rest of the days. Insufficient. CE

Taking both statements together,
we know that on Friday, 50 - 38 =12 books were sold.

Hence Ans is (C).

Is it correct?

the scribble cirlce is the right answer,

i got this one wrong

the question is similar to the one given in link below.

https://www.beatthegmat.com/gmat-prep-od ... html#49756

see Ian's reply and you'll come to know why B is correct in this question.

durgesh79 wrote:the question is similar to the one given in link below.

https://www.beatthegmat.com/gmat-prep-od ... html#49756

see Ian's reply and you'll come to know why B is correct in this question.

Thanks Durgesh. Got the logic.

Continuing on my post, highest sales was on Saturday of 38 copies. So 52 copies are to be sold for the next 6 days where Friday saw the second highest sales and the rest of the 5 days saw the same sales.

So to solve this question, I have to see the highest multiple of 5 near 52.
Suppose I express 52 as = 5*9 + 7

This will mean Friday saw a sales of 7 while rest of the days as 9 which is not correct.

So the next best option will be 5*8 + 12, where Friday saw a sales of 12 and rest of the days as 8. Hence answering my question. Option (B)

Thanks to all for showing the right direction.

Motherjane wrote:We know that Store S sold 90 copies in 7 days and it sold same number of copies for 5 days.

Also we know that greatest number of copies were sold on Saturday and second greatest on Friday.
So for rest of the days of the week except Friday and Saturday, store S sold the same number of copies.

From Statement(1), 8 copies were sold on Thursday.
So the following can be inferred from the above statement:
(1) Highest sales was on Saturday
(2) Second highest was on Friday
(3) For each of the rest of 5 days of the week, 8 copies were sold.

Thus total copies sold on Friday and Saturday = 90- (5 * 8) = 50
But we are not sure whether more than 11 was sold on Friday or not.
For eg the sales might be 10 on Friday and 40 on Saturday (or) 15 on Friday and 35 on Saturday. No information given. Hence insufficient. BCE

From Statement(2), 38 copies was the maximum sold in store S. No information abt the rest of the days. Insufficient. CE

Taking both statements together,
we know that on Friday, 50 - 38 =12 books were sold.

Hence Ans is (C).

Is it correct?

You didn't interpret the question properly. It says, no two days sold the same number of copies, meaning none of the 7 days sold the same number of copies. From statement 2, we know that Friday has to sell > 11 since if we have 11 sales on friday, the rest of the 5 days total doesn't add up to 90(don't forget that Friday is the second highest, so all the other 5 days have to be less then the friday sales)