Pat is reading a book that has a total of 15 chapters. Has Pat read at least 1/3 of the pages in the book?

(1) Pat has just finished reading the first 5 chapters.
(2) Each of the first 3 chapters has more pages than each of the other 12 chapters in the book..

I am able to get the answer by putting numbers but I am unable to frame up an algebraic expression. Also, its taking almost 2 mins for me to solve this type of question which I think is relatively easy. So should I be worried because I got my G-date in next week. Please give an opinion. Thanks a lot friends.

OA is

Hi,

There is no need to form equations and try and solve this as it will be very time consuming.

Just look at it logically.

Question stem : Has Pat read 1/3 the pages in a book containing 15 chapters?

Therefore we have to know something about how many pages he has read as well as the total number of pages in the book (or the number of pages per chapter which would give us the total number of pages).

St. (1) : He has read 5 chapters.

This does not tell us how many pages he has read therefore Insufficient.


St. (2) : Each of the first 3 chapters has more pages than each of the other 12 chapters in the book.

This tells us something about the structure of the book but does not tell us anything about how many pages Pat might have read.


This is where I disagree with the OA and think the answer should be E.


Now, St. (1) and (2) together :

If all the remaining 12 chapters have equal number of pages and the first three have more than those many pages per chapter, then Pat would most certainly have read more than 1/3 of the book had he read the first five chapters.

BUT we are not told anything about the relationship between the other chapters of the book. Therefore we cannot conclude this.

If the first 3 chapters have 10 pages each, the next two have 1 page each, and the last 10 have 8 pages each, the ratio of the pages read to total pages (considering he has read 5 chapters) would be : 32/112.

Now compare this to 1/3 , which can also be written as 32/96.

Since 32/112 is smaller we can safely say that he has not read 1/3 of the pages.

Thus even together, the statements are insufficient.

Therefore, IMO answer is (E).
_________________

Click below to check out some great tips and tricks to help you deal with problems on Remainders!
compilation-of-tips-and-tricks-to-deal-with-remainders-86714.html#p651942

Word Problems Made Easy!
1) Translating the English to Math : word-problems-made-easy-87346.html
2) 'Work' Problems Made Easy : work-word-problems-made-easy-87357.html
3) 'Distance/Speed/Time' Word Problems Made Easy : distance-speed-time-word-problems-made-easy-87481.html

Good question this is. The original poster should not be worried about not solving this question, it is a bit tricky. Keep up the confidence.

Answer should be C.

stmt1.
Pat has finished first 5 chapters. We do not know how many pages are there per chapter and hence the total number of pages. Insuff.

stmt2:
Let p be the number of pages in each of the last 12 chapters.
Let x be the 'extra' pages in each of the first 3 chapters.
So, we have, 3(p+x) pages in first three chapters and 12p pages in last 12 pages.

Total number of pages in the book = 3(p+x)+12p = 3p+3x+12p = 15p+3x

Here, we do not how many pages Pat has read. Insuff

Combining,
Pat has read 3(p+x) + 2p pages = 3p+3x+2p = 5p+3x pages.
1/3 of total pages is (1/3)*(15p+3x) = 5p+x.
Now, x>0 because Pat has read some pages/chapters.
So, 5p+3x > 5p+x. Hence, proved. Sufficient.

Yes, you have a point.

It's alright gmat620.

At least this clears up the confusion now.

Cheers.
_________________

Click below to check out some great tips and tricks to help you deal with problems on Remainders!
compilation-of-tips-and-tricks-to-deal-with-remainders-86714.html#p651942

Word Problems Made Easy!
1) Translating the English to Math : word-problems-made-easy-87346.html
2) 'Work' Problems Made Easy : work-word-problems-made-easy-87357.html
3) 'Distance/Speed/Time' Word Problems Made Easy : distance-speed-time-word-problems-made-easy-87481.html

No problem.. And all the best for your GMAT!
_________________

Click below to check out some great tips and tricks to help you deal with problems on Remainders!
compilation-of-tips-and-tricks-to-deal-with-remainders-86714.html#p651942

Word Problems Made Easy!
1) Translating the English to Math : word-problems-made-easy-87346.html
2) 'Work' Problems Made Easy : work-word-problems-made-easy-87357.html
3) 'Distance/Speed/Time' Word Problems Made Easy : distance-speed-time-word-problems-made-easy-87481.html

This is not the worst case scenario... In fact I am not even sure what the worst case scenario would refer to in this question. Anyway.. that doesn't matter. All we have to see is whether it is possible to get conflicting suggestions or not.

The case you have considered is just one of the possibilities that tells us that he has read more than 1/3 of the pages.

However, there are possibilities which satisfy both St. (1) and St. (2), yet tell us that he has not read even 1/3 of the pages. (refer to my earlier post for an example).

Thus we can conclude that both together are also insufficient.

If you face any further difficulty in my reasoning, just let me know. I will be more than happy to help you out.

Cheers.
_________________

Click below to check out some great tips and tricks to help you deal with problems on Remainders!
compilation-of-tips-and-tricks-to-deal-with-remainders-86714.html#p651942

Word Problems Made Easy!
1) Translating the English to Math : word-problems-made-easy-87346.html
2) 'Work' Problems Made Easy : work-word-problems-made-easy-87357.html
3) 'Distance/Speed/Time' Word Problems Made Easy : distance-speed-time-word-problems-made-easy-87481.html

I will back up sriharimurthy on this one. The answer should be E, because there are quite a few cases in which you could be greater or less than 1/3.

You can refer to my ealier post as well as I have laid out both scenarios.