A school is comprised of 400 people both teachers and students.

Question

A school is comprised of 400 people both teachers and students. If 10 percent of the people are teachers and 400 new people enter the school in the following year, how many of those people must be teachers in order to decrease the percentage of teachers to 5 percent?

A. 50
B. 35
C. 25
D. 10
E. 0

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ManifestDreamMBA · Answer

Let the additional number of teachers be x
With the initial 400, there were 10% = 40 teachers

% of teachers = 40+x/(400+400)
40+x/800=5/100
40+x=40
x=0

Souradeep17 · Answer

10% of 400 =40 teachers initially.
New addition of 400 People.

So, total people 400+400=800
5% of 800 = 40
So, we need not add anyone hence 0 new teachers are required (option E)

Dereno · Answer

Let the students and teachers be denoted as S and T respectively.

400 = S+T

10% of 400 are teachers = 40 teachers and students =360

400 ppl enter the school and the new strength becomes 400+400 = 800.

(40+x)/ (800) = 5/100

Solving, we get 40+x = 40

x = 0

Option E

A school is comprised of 400 people both teachers and students.

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GMAT Problem Solving (PS) Questions

A school is comprised of 400 people both teachers and students.

Prep Toolkit

615 to 715 in 15 Days (Ria's Strategies)

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745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards