hwks06

gmat0805, pardon my dumb question. how did you get: Also to note n(P) and n(T) each greater than or equal to 60?? Thanks

think of the 6 volumes as a, b, c, d, e, f mean = x = (a+b+c+d+e+f)/6 std. deviation = {[(x~a)^2+(x~b)^b+(x~c)^2....+(x~f)^2]/6}^1/2 = 10 now if you take out 30% of the vol. then you are left with 70% in each of them a' = 0.7a ....and so on new mean = y = (0.7a + 0.7b ....+0.7f)/6 = 0.7x std. deviation = {[(y~a')^2+(y~b')^b+...(xy~f')^2]/6}^1/2 == {[0.7(x~a)^2 + .....0.7(x~f)^2]/6}^1/2 sub'ing value given as 10 gallon we get the new std. deviation (B) gives you the mean but not anythine else. So (A)

wisenhimer are you asking for the std. deviation at the end of the expt. or the std. volume? if its the std. deviation then the answer is (A).

2) I am saying its A. i) t both t and k being -ve, product kt > 0 so it has be either A or D ii) k if k = 0.9 then if t = 1 kt = 0.9 k = -1 then t can be either a +ve or -ve number > -1. So we cannot really tell. So its (A) 1) I think its (B) if by std volume of water means the total vol. of water in all 6 tanks at the end of the expt.

Pardon the dumb question but after answering a few of the OG DS questions I am concerned with my strike rate. In a numbers question like: Is Z an integer? a) condition 1) b) condition 2) Is the expectation that: a) the conditions answer "yes Z is an integer" or b) the conditions answer "yes Z is an integer or no Z is not an integer" i.e. given the conditions can I tell if Z is an integer or not. there is a subtle difference in the two. In the second I am asking if the 2 conditions or each of them allow me to determine if Z is an integer or not. In the 1st Z has to be an integer or the answer is {E}. Thanks a lot for setting me straight. -HS

greycellz, in your post you mention the DS posted by nuthan? Do you mean the individual Qs that nuthan posts or is there a consolidated doc somewhere in one of the posts? BTW congrats on the great score. Good luck with the apps. TIA