During a recent survey of two middle school classrooms, 1/3 of the students reported that they bring their lunch to school. Another 1/4 reported that they buy their lunch in the cafeteria and 1/6 reported going home for lunch. The remaining 18 students reported that they don't eat lunch. How many students are in the two classes?

Let's start by finding the fraction of students who bring their lunch:

1/3 of the students bring their lunch.

Now let's find the fraction of students who buy their lunch:

1/4 of the students buy their lunch.

And the fraction of students who go home for lunch:

1/6 of the students go home for lunch.

We can add these three fractions together to find the fraction of students who eat lunch in some way:

1/3 + 1/4 + 1/6 = 6/12 + 3/12 + 2/12 = 11/12

This means that 1/12 of the students don't eat lunch (since 11/12 + 1/12 = 1). We can use this information to set up an equation:

18 = (1/12)x

where x is the total number of students. Solving for x, we get:

x = 216

So there are 216 students in the two classes.

Let's start by finding the fraction of students who bring their lunch to school. We are told that 1/3 of the students bring their lunch.

Let's represent the total number of students in the two classes as x.

So, the number of students who bring their lunch is 1/3 * x.

Now, let's find the fraction of students who buy their lunch in the cafeteria. We are told that 1/4 of the students buy their lunch.

So, the number of students who buy their lunch is 1/4 * x.

Next, let's find the fraction of students who go home for lunch. We are told that 1/6 of the students go home for lunch.

So, the number of students who go home for lunch is 1/6 * x.

Finally, we are told that 18 students reported that they don't eat lunch.

Therefore, the equation to represent the problem is:

1/3 * x + 1/4 * x + 1/6 * x + 18 = x

To solve this equation, we need to find a common denominator for the fractions.

The common denominator for 3, 4, and 6 is 12.

Multiplying the equation by 12, we get:

4x + 3x + 2x + 216 = 12x

Combining like terms, we have:

9x + 216 = 12x

Subtracting 9x from both sides, we get:

216 = 3x

Dividing both sides by 3, we have:

x = 72

Therefore, there are a total of 72 students in the two classes.