Chap11

I live in Vasundhara Enclave and will be taking GMAT in April 2011. Anybody interested in forming a study group, please revert back to me. What I am interested in is that we share the information available to us and clear each other's doubts. It does not have to be on daily basis and we can meet weekly or twice a month.

Bobogee do we know how many types of different entrees we have? Thanks.

I do not know whether you are still preparing or not but I have started preparing 2 weeks before and would like to exchange notes with you on GMAT material. Please let me know either way. By the way I also live in east delhi.

onetwofour and andspeed , Thanks so much for the detailed explanation. I really appreciate it!

The Earth’s rivers constantly carry dissolved salts into its oceans. Clearly, therefore, by taking the resulting increase in salt levels in the oceans over the past hundred years and then determining how many centuries of such increases it would have taken the oceans to reach current salt levels from a hypothetical initial salt-free state, the maximum age of the Earth’s oceans can be accurately estimated. Which of the following is an assumption on which the argument depends? A. The quantities of dissolved salts deposited by rivers in the Earth’s oceans have not been unusually large during the past hundred years. B. At any given time, all the Earth’s rivers have about the same salt levels. C. There are salts that leach into the Earth’s oceans directly from the ocean floor. D. There is no method superior to that based on salt levels for estimating the maximum age of the Earth’s oceans. E. None of the salts carried into the Earth’s oceans by rivers are used up by biological activity in the oceans. In my opinion, A can be discarded because even if the salt quantity being deposited is large, it would mot make any difference to our assumption. B can be discarded because it is never said in the paragraph that the all the rivers on earth have the same concentration of salt at any given time. C can be discarded because there is nothing like that in the paragraph. D is better because of the two words, “clearly” and “accurately”, being used in second sentence of the paragraph. E is also a preferred option because if it is true then it would help us estimate the age more accurately. So answer is D according to me. I am a new comer here so please give me some feedback about my thought process. Thanks.

Thanks Onetwofour. Actually I was confused at first when I saw this question in the book but then you told me the same reason and the same answer and now I want to believe it. So I am good now. Thanks so much!

sankarbalaji, pretty smart explaination!

sankarbalaji, I am with you in this.

Pzazz12, Would you explain to me what does it mean when you say "injections that can be defined from A to B". Thanks.

This is what I came up with! According to the condition # 1, for any integer in P, the sum of 3 and that integer is also in P, and we also know 3 is in P. So what that means is that (3+3) = 6 is also a member of P. Then (3+6) = 9 is also a member of P. In the same way, (9+3) =12 is also a member of P and so on. Condition 1 is sufficient in itself. Now according to the condition # 2, for any integer in P, that integer minus 3 is also in P. Again 3 is in P so what that means is (3-3) = 0 but then P is a set of positive integers so this chain ends right here. Condition #2 is not sufficient in itself. By the way I also came up with some other answer first and then I looked at the answer given which made me realize the mistake in my calculation. Please let me know what you think.

Please forgive me if this is silly! Did John go to beach yesterday? 1) If John goes to the beach, he will be sunburned the next day. 2) John is sunburned today. I will let you know about my doubt as soon as somebody answers it. Thanks.

That was the best explanation Makumajon. I was confused between B & D but then I saw your reply and It was crystal clear to me. Thanks so much.

Good job! Keep it up! By the way which programs are you applying to!