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\(E_1​\): The number of employees on the first day of the year.
\(E_2\)​: The number of employees on the last day of the year.
L: The number of employees who left the company during the year.

­Turnover Rate= \(L \div \frac{E_1​+E_2​​}{2}= 0.25\)

>>> \(L = 0.125 * (E_1​+E_2​)\)


Requirements
S1 ==> S2
But it cannot be S2 ==> S1


=> Statement 1: All and only those who were employees at the company on the first day of last year were employees on the last day of last year.
=> Statement 2: Last year, the number of employees on the first day of the year was equal to the number of employees on the last day of the year.


S1: If all and only those who were employees on the first day were employees on the last day:

No new employees joined the company during the year.

The number of employees who left equals the number of employees who joined, which is zero since no new employees joined.

So, E1=E2​, and everyone who left must have been among the initial employees. (i.e. S2)


S2: If the number of employees on the first day of the year was equal to the number on the last day of the year:

E1=E2

Given the turnover rate of 25%, we have: L=0.25×E1

But we cannot jump to S1. The company could have had new employees join and the same number (but a different set, which is a part of E1) leave, maintaining the total number equal.
 ­
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kkannan2
Hi KarishmaB - what's your logic in picking numbers for this question? In other words, how did you know to test out the numbers that you did (4 employees at the company to start, 1 joins and 1 leaves and 9 employees at the company to start, 2 leave and 0 join)? I find it tough to pick numbers for such TPA questions and generally waste time on that. Any tips or suggestions would be appreciated! Thanks!
­I want to keep the numbers small, simple but realistic. So 4 and 1 are the best options. They are easy to evaluate.
25 and 100 would lead to chaos.

Also, it is much easier to explain why certain options work and why others don't. But picking the options and checking in an exam setup will be hard. Such a question where looking for the first thread is hard should be bookmarked. Return to it if you have time. Penalty of an incorrect answer here would be negligible.
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Kindly explain the meaning of the term "all and only those"

My understanding is that it means that "all and only those employees who were employees of company on first day of last year" means that only those employees who were employees of company.

My understanding is that it means that if a, b, c were employees the only possiblity for last day are "a" or "b" or "c" or "a and b" or "a and c" or "b and c" or "a, b and c". There is no mention of the word number . Why are you all equating all and those to number of employees­
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desertEagle
Kindly explain the meaning of the term "all and only those"

My understanding is that it means that "all and only those employees who were employees of company on first day of last year" means that only those employees who were employees of company.

My understanding is that it means that if a, b, c were employees the only possiblity for last day are "a" or "b" or "c" or "a and b" or "a and c" or "b and c" or "a, b and c". There is no mention of the word number . Why are you all equating all and those to number of employees­
­The phrase "all and only those" means that everyone who was an employee on the first day of last year remained an employee on the last day of the year, and no one else became an employee during that time.

In simpler terms:


  • "All" means every person who was an employee on the first day continued to be an employee on the last day.
  • "Only those" means no one else (who wasn’t an employee at the start) became an employee by the end of the year.

So, if a, b, and c were employees at the beginning, then the only people who could still be employees at the end of the year are a, b, and c—no one else.

This isn't about the "number" of employees changing, but rather about the specific individuals who were employees throughout the year.­
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Hi KarishmaB,

I chose the option E as St1 and Option B as St2. I know this is a wrong answer but I don't know why this is wrong.
Can you help me with this?
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imAman
Hi KarishmaB,

I chose the option E as St1 and Option B as St2. I know this is a wrong answer but I don't know why this is wrong.
Can you help me with this?






KarishmaB
chetan2u
­
All Data Insight question: TPA [ Official Guide DI Review 2023-24]
A certain company defines its annual labor turnover rate as the number of employees who left the company during the year divided by the average of the number of employees on the first day of the year and the number of employees on the last day of that year. Last year, the company had a labor turnover rate of exactly 25%.

Assuming that the information above is true, select for Statement 1 and for Statement 2 the statements such that if Statement 1 is true, then Statement 2 must be true, but it could be the case that Statement 2 is true and Statement 1 is false. Make only two selections, one in each column.­
The turnover rate is 25% i.e. 1/4

So various scenarios are possible.

Beg of year - 4 people
1 left, 1 joined
End of year - 4 people

Beg of year - 9 people
2 left, 0 joined
End of year - 7 people

etc...


Why (D) and (E) work (ANSWER):

(D) All and only those who were employees at the company on the first day of last year were employees on the last day of last year.

Consider the 1st example above. The 4 who were at the beginning were the ones at the end too. That is all. It is certainly possible. One person joined and he was the one who left.

(E) Last year, the number of employees on the first day of the year was equal to the number of employees on the last day of the year.

Has to be true because all and only those who were on the 1st day were on the last day too. No reductions. No extra people.


Why (B) and (E) do not work:

(B) Exactly 25% of the employees working at the company on the first day of last year left the company last year.

Beg of year - 100 people
25 of these 100 left, 70 joined and 5 of these left
End of year - 140 people
Turnover Rate = 30/120 = 25%

(E) Last year, the number of employees on the first day of the year was equal to the number of employees on the last day of the year.

Not true as per the illutration above. ­

Think about it: Say there were 100 people on the first day and 100 people on the last day. (Option (E) is true)

On the first day, the employees are E1 to E100.

Say 20 of these left - from E1 to E20. So now there are 80 employees (E21 to E100)
Say 25 new people joined (E101 to E125). So now there are 105 employees. (E21 to E125)
Now say 5 of these new people left (E121 to E125 left).

There are again 100 employees - from E21 to E120

Is (B) true?
(B) Exactly 25% of the employees working at the company on the first day of last year left the company last year.

No. Only 20% of the employees working at the company on the first day of last year left the company last year.

That is why (E) - (B) doesn't work.
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Hello, thank you for the solution. I have a question: in S1,
"No new employees joined the company during the year.

The number of employees who left equals the number of employees who joined, which is zero since no new employees joined." In this case, shouldn't the turnover rate be zero as no one left the company
Gemmie
\(E_1\): The number of employees on the first day of the year.
\(E_2\): The number of employees on the last day of the year.
L: The number of employees who left the company during the year.

­Turnover Rate= \(L \div \frac{E_1+E_2}{2}= 0.25\)

>>> \(L = 0.125 * (E_1+E_2)\)


Requirements
S1 ==> S2
But it cannot be S2 ==> S1


=> Statement 1: All and only those who were employees at the company on the first day of last year were employees on the last day of last year.
=> Statement 2: Last year, the number of employees on the first day of the year was equal to the number of employees on the last day of the year.


S1: If all and only those who were employees on the first day were employees on the last day:

No new employees joined the company during the year.

The number of employees who left equals the number of employees who joined, which is zero since no new employees joined.

So, E1=E2, and everyone who left must have been among the initial employees. (i.e. S2)


S2: If the number of employees on the first day of the year was equal to the number on the last day of the year:

E1=E2

Given the turnover rate of 25%, we have: L=0.25×E1

But we cannot jump to S1. The company could have had new employees join and the same number (but a different set, which is a part of E1) leave, maintaining the total number equal.
­
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You could have the same employees who joined also be the ones who left, which would still allow a 25% turnover rate while keeping the statements true.
NoeticImbecile
Hello, thank you for the solution. I have a question: in S1,
"No new employees joined the company during the year.

The number of employees who left equals the number of employees who joined, which is zero since no new employees joined." In this case, shouldn't the turnover rate be zero as no one left the company
Gemmie
\(E_1\): The number of employees on the first day of the year.
\(E_2\): The number of employees on the last day of the year.
L: The number of employees who left the company during the year.

­Turnover Rate= \(L \div \frac{E_1+E_2}{2}= 0.25\)

>>> \(L = 0.125 * (E_1+E_2)\)


Requirements
S1 ==> S2
But it cannot be S2 ==> S1


=> Statement 1: All and only those who were employees at the company on the first day of last year were employees on the last day of last year.
=> Statement 2: Last year, the number of employees on the first day of the year was equal to the number of employees on the last day of the year.


S1: If all and only those who were employees on the first day were employees on the last day:

No new employees joined the company during the year.

The number of employees who left equals the number of employees who joined, which is zero since no new employees joined.

So, E1=E2, and everyone who left must have been among the initial employees. (i.e. S2)


S2: If the number of employees on the first day of the year was equal to the number on the last day of the year:

E1=E2

Given the turnover rate of 25%, we have: L=0.25×E1

But we cannot jump to S1. The company could have had new employees join and the same number (but a different set, which is a part of E1) leave, maintaining the total number equal.
­
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