You had helped me with a similar question.

Question

This one says :
A whole seller supplies 90 books while he was ordered to send 80 books by a retailer. If 15%trade discount was given, what was the net discount to the retailer?

I solved this one in the similar way to the one you helped me with but the answer doesn't match with the book. My book says answer is 27.5 % but I got 24.4%. There Was no answer for the one before this(the book had not printed the answer) for the previous question. Plzzzz help

Answer 1

I just copied my previous solution and changed the numbers:

Suppose that the cost of each of the original books was $x per book
So the cost was 80x
He got a 15% discount, so the cost was (.85)80x
= 68x
but for 68x he actually got 90 books
so the cost of each book was only 68x/90
= 34x/45

As a percentage: (34x/45) / x
= .7555.. or appr 75.6 %

which would be an effective discount of 24.4%

----- the same as yours. mmmhhhh, I am very confident in my logic to this question.
I even gave an example showing that in my earlier post. I assume you are in the US. I am in Canada, but I don't if the definition of trade discount is different.

Answer 2

I reckon the book has a misprint answer because, my friends said that they had the same concept and had done the solution the same way. Thanks for the help any way reiny. And anyway I am from Nepal not USA.