Problem Solving

In a certain investment club, 36 members invest in domestic
stocks or foreign stocks or both. If 8 members do not invest in
domestic stocks, how many members invest in both domestic
stocks and foreign stocks?

(1) Of the 36 members, 14 do not invest in foreign stocks.
(2) A total of 22 members invest in foreign stocks.

I had E because there was no information for neither. OA suggest that neither is implied. I disagree. Unless it said there's only 36 member in the club, you can't make that assumption. Am I wrong? Most likely, please

Domestic Not-D

F x y

NF z k

"36 members invest in....." to me that means x+y +z= 36 but says nothing about K. The the "8 member did not..." means y+k=8. Both choices are insufficient.

gmatusa2010 wrote:In a certain investment club, 36 members invest in domestic
stocks or foreign stocks or both. If 8 members do not invest in
domestic stocks, how many members invest in both domestic
stocks and foreign stocks?

(1) Of the 36 members, 14 do not invest in foreign stocks.
(2) A total of 22 members invest in foreign stocks.

I had E because there was no information for neither. OA suggest that neither is implied. I disagree. Unless it said there's only 36 member in the club, you can't make that assumption. Am I wrong? Most likely, please

Domestic Not-D

F x y

NF z k

"36 members invest in....." to me that means x+y +z= 36 but says nothing about K. The the "8 member did not..." means y+k=8. Both choices are insufficient.

I know that may sound a little bit ambiguous, however If had to guess, I would also assume "neither" is implied here. The only reason is that the information is about 36 people of an investment club. While there is some possibility that some of the members (apart from these 36 members) of the club do not invest or are investing in some other stocks, since the author specifically mentions about a particular subset : 36 members invest in domestic stocks or foreign stocks or both , It is most likely implied.
Making it clear would have been better, however it is implied. I hope you got the point I tried to make.

gmatusa2010 wrote:In a certain investment club, 36 members invest in domestic
stocks or foreign stocks or both. If 8 members do not invest in
domestic stocks, how many members invest in both domestic
stocks and foreign stocks?

(1) Of the 36 members, 14 do not invest in foreign stocks.
(2) A total of 22 members invest in foreign stocks.

I had E because there was no information for neither. OA suggest that neither is implied. I disagree. Unless it said there's only 36 member in the club, you can't make that assumption. Am I wrong? Most likely, please

Domestic Not-D

F x y

NF z k

"36 members invest in....." to me that means x+y +z= 36 but says nothing about K. The the "8 member did not..." means y+k=8. Both choices are insufficient.

Is the OA [spoiler]A?[/spoiler]

E it is

Both option provides same info and is insufficient.

See the table below:Given

FY FN Total
DY x

DN
28 8 36

Using option A:

FY FN Total
DY x 22

DN 14
28 8 36

Same using option B, as given Dn Dy can be calculates. So insufficient.


Here D : Domestic, F: Foreign, Y : Yes N No

Is OA A?

The total members of the club is 36 since the question stem speficially states that 36 members invest in domestic, foreign, or both. We can set up a venn diagram or a grid to solve the answer using our 36 members. There is an equation that we can use: PA + PB - PA & PB (the sum of shared items) = total. So we take 28 + 22 - X = 36. X = 14 or 14 members invest in both domestic and foreign. Since statements 1 and 2 state the same answer but in different forms we can narrow the answer choices down to two, D and E. Since we can solve the answer either statement our answer is D. Also, we get a breakdown of 14 members investing soley in domestic and 8 members investing solely in foreign with 14 members investing in both domestic and foreign for a total of 36 members. I hope I explained this clear.

at first i thought E but i left out some information from the problem statement. Now im going with D each sufficient

From stem we can say that there are 36 total people.. and we can also plug 8 in the no domestic box

Statment 1 says 14 do not invest in Foreign so plug 14 into No foreign box since we know neither is 0 we know have a total for No Foreign and we can calculate total for yes foreign 22 - 8 = 14 so 14 goes in the Yes yes box...

Statement 2 gives similar information so D... Does anyone agree with my assesment if not please help correct me.


..................................yes Domestic...........No Domestic..............Total
Yes Foreign..................14............................8..............................22
No Foreign....................14............................0...............................14

Total...............................................................................................36

D........................ND
F.............14+X....................8-x...........22
NF.............14.......................x..............14+X
--------------------------------------------------------
................28+X....................8...............36+X


Ron,

What do you mean the result is the same way? I tried putting in the X as you said. YOu have to find the value of 14+X. You still don't know X so you cant determine the value. I think there is OG 11 problem where the neither is not implied in the same wording. I will try to dig that up.

lunarpower wrote:

gmatusa2010 wrote:I had E because there was no information for neither. OA suggest that neither is implied. I disagree. Unless it said there's only 36 member in the club, you can't make that assumption. Am I wrong? Most likely, please

the original wording says:
36 members invest in domestic stocks or foreign stocks or both
this means that these 36 people constitute everyone who does at least one of those things. since these people are the only people mentioned in the entire problem, you can just disregard the possible presence of individuals who are "neither" -- since they just don't factor into the problem.
in other words, the entire universe of people discussed in the problem -- the total of 36 people -- includes only people who invest in at least one of these instruments. therefore, you can draw a grid with 36 in the lower right corner, and 0 in the middle box (the box that corresponds to "no domestic, no foreign").

alternatively, if you insist on including the possible "neither" people -- even though they don't factor into the problem in any tangible way -- then you could put an 'x' in the "neither" box. but, then, the lower right corner (grand total) would have to be (36 + x) rather than just 36, and your results should work out the same way.