Sixty percent of the people who responded to a company's advertisement

let x is the total number of respondents
number of people interviewed on the phone = \(3 = \frac{20}{100}*\frac{60}{100}*x\)
so \(x = \frac{3*100*100}{20*60} = 25\)

Let total number of people who responded to advertisement be \(= T\)

\(60\)% of \(T\) were interviewed on phone \(= \frac{60}{100}*T\)

\(20\)% of \(60\)% of \(T\) were asked to come to the company for personal interview, that is \(3\).

Therefore; \(20\)% of \(60\)% of \(T = 3\)

\(\frac{20}{100}*\frac{60}{100}*T = 3\)

\(T = \frac{3*100*100}{20*60} = 25\)

Answer C

Solution

Given:

• 60% of the people who responded to a company’s advertisement for a job opening were interviewed over the phone.
• Among the people who were interviewed over the phone, 20% or 3 people were asked to come for a personal interview.

To find:

• The number of people responded to the original advertisement.

Approach and Working:
20% of people called = 3

• Therefore, the number of people called = 3 x 5 = 15

60% of the people responded = 15

• Therefore, the number of people responded = 15 x 5/3 = 25

Hence, the correct answer is option C.

Answer: C


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3 people = 20*x/100
x= 15 people called for phone interview
15= 60*x/100
x = 25 ; had applied /responded to ad
IMO C

Hi All,

We're told that 60% of the people who responded to a company's advertisement for a job opening where interviewed over the phone and 20% of those interviewed over the phone (re: 3 people), were asked to come to the company for a personal interview. We're asked for the total number of people who responded to the advertisement. This question can be solved in a couple of different ways, including by TESTing THE ANSWERS.

Let's TEST Answer B first: 20 people
IF.... 20 people responded to the advertisement...
then (.6)(20) = 12 people were interviewed over the phone...
and (.2)(12) = 2.4 people had a personal interview.
This is NOT a match for what we were told (it's supposed to be 3 people, not "2.4 people"). This answer is too small, so we need MORE people to start with. Eliminate Answers A and B.

Under normal circumstances, we would TEST Answer D next.... but that Answer is DOUBLE Answer B (40 vs. 20) and that seems to be a big increase considering how closer 2.4 is to 3. So let's TEST Answer C next...

Answer C: 25 people
IF.... 25 people responded to the advertisement...
then (.6)(25) = 15 people were interviewed over the phone...
and (.2)(15) = 3 people had a personal interview.
This IS an exact match for what we were told, so this MUST be the answer!

Final Answer:

GMAT assassins aren't born, they're made,
Rich

We can create the following equation:

0.6 x 0.2 x T = 3

0.12T = 3

12T = 300

T = 25

Answer: C
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