Where does in the question it is written that Juan bought books of $175?Suyog wrote:Using both (1) and (2):
If we say that, total cost of hardcover books that Juan bought $175 and the total cost of books is less than 260 then Juan can not buy more than 10 paperback books. So juan bought 6 Hardcover books.
Choose(c).
The question doesn't ask how many paperback books he bought. It asks how many hardcover books he bought. Suyog's solution is correct; if he spends $175 or more on hardcovers, the other conditions in the question can't be true. So he must have spent $150 on hardcovers - that is, he must have bought 6 hardcover books.codesnooker wrote: And in this, he can be either 10, 11, 12, or 13 paperback books.
You can solve in this waycodesnooker wrote:Any Suggestion?
Can you plz. explain in details how you reached at this $175.Ian Stewart wrote:The question doesn't ask how many paperback books he bought. It asks how many hardcover books he bought. Suyog's solution is correct; if he spends $175 or more on hardcovers, the other conditions in the question can't be true. So he must have spent $150 on hardcovers - that is, he must have bought 6 hardcover books.codesnooker wrote: And in this, he can be either 10, 11, 12, or 13 paperback books.
Only one thing to object: solving the 8x+25y<260 and x>10 sistem will result in y<6.88, otherwise your explanation allows 2 solutions 6 and 7 (7<7.2).olika wrote:You can solve in this waycodesnooker wrote:Any Suggestion?
x is the number of paperback books
y is the number of hardcover books
we have:
the price of a paperback book is $8,
the price of a hardcover book - $25,
x>10
from the (1) we'll get: 25y greater or equal to 150
from the (2): 8x+25y<260
Solving (1), you'll get y greater or equal 6 -----> insuff.
As for (2), we have a set of equations: 8x+25y<260 and x>10. Solving this system, you'll get y<7.2 . So y should be less than 7 -----> insuff.
Statements taking together are suff.: 6<=y<7. So, y should be equal to 6.
The ans. C.
Hardcovers cost $25 each. If he buys 7 or more hardcovers, he would spend at least 7*25 = $175. That isn't possible if you use the information from both statements, so he must have bought fewer than 7 hardcovers.gmattester wrote:Can you plz. explain in details how you reached at this $175.Ian Stewart wrote:The question doesn't ask how many paperback books he bought. It asks how many hardcover books he bought. Suyog's solution is correct; if he spends $175 or more on hardcovers, the other conditions in the question can't be true. So he must have spent $150 on hardcovers - that is, he must have bought 6 hardcover books.codesnooker wrote: And in this, he can be either 10, 11, 12, or 13 paperback books.
and even post on the forum also. 
Sorry for the trouble guys. I got it.
