Difference between revisions of "1985 AJHSME Problems/Problem 23"

(Solution)
(Solution 2 (Similar to above solution))
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==Solution 2 (Similar to above solution) ==
 
==Solution 2 (Similar to above solution) ==
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Each teacher teaches <math>4</math> classes and each class has <math>30</math> students, so each teacher teaches <math>120</math> students in one class.
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So, to teach five classes, there has to be <math>5</math> teachers, but there is <math>1200</math> students, so multiply by <math>\frac{1200}{120}</math> which is <math>50</math>, or <math>\boxed{\textbf{(E)}\ 50}</math>
  
 
==See Also==
 
==See Also==

Revision as of 18:16, 6 October 2024

Problem

King Middle School has $1200$ students. Each student takes $5$ classes a day. Each teacher teaches $4$ classes. Each class has $30$ students and $1$ teacher. How many teachers are there at King Middle School?

$\text{(A)}\ 30 \qquad \text{(B)}\ 32 \qquad \text{(C)}\ 40 \qquad \text{(D)}\ 45 \qquad \text{(E)}\ 50$

Solution

If each student has $5$ classes, and there are $1200$ students, then they have a total of $5\times 1200=6000$ classes among them.

Each class has $30$ students, so there must be $\frac{6000}{30}=200$ classes. Each class has $1$ teacher, so the teachers have a total of $200$ classes among them.

Each teacher teaches $4$ classes, so if there are $t$ teachers, they have $4t$ classes among them. This was found to be $200$, so \[4t=200\Rightarrow t=50\]

This is answer choice $\boxed{\text{E}}$

Solution 2 (Similar to above solution)

Each teacher teaches $4$ classes and each class has $30$ students, so each teacher teaches $120$ students in one class.

So, to teach five classes, there has to be $5$ teachers, but there is $1200$ students, so multiply by $\frac{1200}{120}$ which is $50$, or $\boxed{\textbf{(E)}\ 50}$

See Also

1985 AJHSME (ProblemsAnswer KeyResources)
Preceded by
Problem 22
Followed by
Problem 24
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
All AJHSME/AMC 8 Problems and Solutions


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