Last year at an accounting firm, accountants made up 40%...

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Last year at an accounting firm, accountants made up 40% of the total employees. This year, 50% of these accountants left for another company, and new accountants, which amounts to 50% of the total employees left, joined the company. What percent of the total employees are accountants this year?

A. 10%
B. 20%
C. 25%
D. 30%
E. 50%

The OA is E.

I need help with this PS question. Please, can any expert assist me with it? Thanks.
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by ErikaPrepScholar » Thu Nov 02, 2017 5:18 am
A really good strategy when working with a lot of percents is to plug in a number that is easy to work with and use it to solve.

Let's say we start with 100 total employees. This means that 40 of those employees are accountants.

This year 50% of those 40 accountants left - so 20 accountants left, leaving us with 80 total employees, 20 of whom are accountants.

Then, we get new accountants. We know that the number of new accountants is equal to 50% of the total number of employees left, which we know is 80. So there are 40 new accountants. This gives us 120 total employees, 60 of whom are accountants.

60 is 50% of 120, so 50% of the total employees are accountants.

Remember, scenario problems like this should work with any number you choose, so plugging in an easy number like 10 or 100 is often easier than thinking about percentages in the abstract.
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by Scott@TargetTestPrep » Fri Nov 01, 2019 6:57 pm
swerve wrote:Last year at an accounting firm, accountants made up 40% of the total employees. This year, 50% of these accountants left for another company, and new accountants, which amounts to 50% of the total employees left, joined the company. What percent of the total employees are accountants this year?

A. 10%
B. 20%
C. 25%
D. 30%
E. 50%

The OA is E.

I need help with this PS question. Please, can any expert assist me with it? Thanks.
We can let the total number of employees = E. Thus, the number of accountants is 0.4E.

We are given that this year, 50% of these accountants left for another company, so 0.5(0.4E) = 0.2E of the accountants left for another company. Thus, there are 0.8E left at the company.

Now, since the number of new accountants who joined the company amounts to 50% of the total employees left, the number of new accountants added to the company is 0.5(0.8E) = 0.4E.

Thus, this year we have a total of 0.4E - 0.2E + 0.4E = 0.6E accountants and a total of E - 0.2E + 0.4E = 1.2E employees. So the percent of the total employees who are accountants this year is:

0.6E/1.2E = 0.6/1.2 = 1/2 = 50%

Alternate Solution:

Let's let 100 = the number of employees last year. Thus, 40 of them were accountants last year. This year, 50% of the accountants (20 accountants) left, and thus, there were 80 employees left (including 20 accountants). New accountants were hired, and they constituted half of those 80 remaining employees, so the number of accountants hired is 40. So now, there are 80 + 40 = 120 employees, and the number of accountants is 20 + 40 = 60 accountants. Thus, this year, the percent of accountants is 6/120 = 0.5 = 50%.

Answer: E

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by [email protected] » Tue Nov 26, 2019 12:47 pm
Hi All,

This is an awkwardly-worded question, but it can be solved by TESTing VALUES.

To start, let's set the TOTAL number of employees at 100. Since 40% of those employees are accountants, we have 40 accountants (out of 100 employees).

Next, we're told that 50% of the ACCOUNTANTS left for another company - thus 20 (of the 40) left. This leaves 80 total employees, of which 20 are accountants.

Then a group of NEW accountants, equal to 50% of the CURRENT number of employees, joined the company. Since there were 80 current total employees, that 50% increase represents 40 NEW accountants. This brings the total number of employees up to 120 and the total number of accountants up to 60. The question asks for the percentage of total employees that are now accountants....

60/120 = 1/2 = 50%

Final Answer: E

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