When an international relief agency extended loans to 28

Question

When an international relief agency extended loans to 28 countries, the unemployment rate dropped in some of the countries, and the per-capita GDP rose in some of the countries. In how many of the countries did the unemployment rate drop?

(1) In 10 of the countries, the unemployment rate did not drop, and the per-capita GDP did not rise.
(2) In 12 of the countries, the per-capita GDP rose but the unemployment rate did not drop.

shreerajp99 · Answer

Use double sets matrix here.I cant show u here but make column using Unemployment rate dropped and nonemployment did not drop.
Make row for GDP rose and GDP did not rise.
Statement 1 isnt sufficient since we get just the number of countries in which unemployment rate did not drop and GDP did not rise.
Statement 2 gives just the number of countries in which GDP rate rose but unemployment did not drop. Insufficient.

Combining 1 and 2,we get number of countries in which unemployment did not drop(22) and thus 28-22 =6 gives us the required answer.

Thanks,
Shreeraj

Pansi · Answer

A- Countries where unemployment dropped
B- Countries where GDP increased
E- Countries where neither unemployment dropped nor GDP increases
We need just A
Total = A+B+E-AnB ---> 28=A+B+E-AnB

Statement 1 - Just gives E.
Statement 2- Just gives B-AnB

Combined---> 28=A+12+10 ---> A=6

Bunuel · Answer

When an international relief agency extended loans to 28 countries, the unemployment rate dropped in some of the countries, and the per-capita GDP rose in some of the countries. In how many of the countries did the unemployment rate drop?

Given that  {total}={unemployment rate dropped}+{GDP rose}-{both}+{neither}  -->  28={unemployment rate dropped}+{GDP rose}-{both}+{neither} .

Question:  {unemployment rate dropped}=?

(1) In 10 of the countries, the unemployment rate did not drop, and the per-capita GDP did not rise.  {neither}=10  -->  28={unemployment rate dropped}+{GDP rose}-{both}+10 . Not sufficient.

(2) In 12 of the countries, the per-capita GDP rose but the unemployment rate did not drop -->  {GDP rose}-{both}=12  -->  28={unemployment rate dropped}+12+{neither} . Not sufficient.

(1)+(2)  28={unemployment rate dropped}+12+10  -->  {unemployment rate dropped}=6 . Sufficient.

Answer: C.

Hope it's clear.

PathFinder007 · Answer

Hey Bunuel,

could you please explain me following statement

In 12 of the countries, the per-capita GDP rose but the unemployment rate did not drop -->  {GDP rose}-{both}=12  -->  28={unemployment rate dropped}+12+{neither} . Not sufficient.

I want to know why we are considering {both} here.

Bunuel · Answer

{GDP rose} includes ALL the countries where GDP rose, so the countries where GDP rose and unemployment rate dropped as well the countries where GDP rose and unemployment rate did not drop: 
{GDP rose} = {GDP rose and unemployment rate dropped} + {Only GDP rose} = {Both} + {Only GDP rose}

So, the number of countries where GDP rose but the unemployment rate did not drop = the total number of countries where GDP rose minus those countries where GDP rose and unemployment rate dropped: 
{Only GDP rose} = {GDP rose} - {Both} --> 12 = {GDP rose}-{both}.

Hope its clear.

hideyoshi · Answer

Using the table method, one can come to conclusion that both the statements are needed to arrive at an answer.

Table attached...

sarahfiqbal · Answer

This question (once you know how to tackle it) its easy. When I first read it, I thought it was a mean/median type question and suddenly just freaked out because I had no idea what to do. So I guessed and fair enough got it wrong. Looking at the explanations, it is just a simple double matrix question. Took me 28 secs to do the question once I realised this. I am wondering why I didn't think of double matrix in the first place? I feel like my thinking process isn't right. How to fix this? Do you just attempt more practice problems?

I am a little frustrated with myself because of that. =_=

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When an international relief agency extended loans to 28

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When an international relief agency extended loans to 28

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