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The students of a class are made to stan...

The students of a class are made to stand in rows. If 3 students are extra in a row, there would be 1 row less. If 3 students are less in a row, there would be 2 rows more. Find the number of students in the class.

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To solve the problem, we need to set up equations based on the information given. Let's break it down step by step. ### Step 1: Define Variables Let: - \( x \) = number of students in each row - \( y \) = number of rows ### Step 2: Formulate the First Equation According to the problem, if 3 students are added to each row, there would be 1 row less. This can be expressed mathematically as: \[ (x + 3)(y - 1) = xy \] Expanding this gives: \[ xy - x + 3y - 3 = xy \] Cancelling \( xy \) from both sides, we get: \[ -x + 3y - 3 = 0 \] Rearranging this, we have: \[ x - 3y + 3 = 0 \quad \text{(Equation 1)} \] ### Step 3: Formulate the Second Equation Next, if 3 students are removed from each row, there would be 2 rows more. This can be expressed as: \[ (x - 3)(y + 2) = xy \] Expanding this gives: \[ xy + 2x - 3y - 6 = xy \] Cancelling \( xy \) from both sides, we get: \[ 2x - 3y - 6 = 0 \] Rearranging this, we have: \[ 2x - 3y - 6 = 0 \quad \text{(Equation 2)} \] ### Step 4: Solve the Equations Now we have two equations: 1. \( x - 3y + 3 = 0 \) 2. \( 2x - 3y - 6 = 0 \) We can solve these equations simultaneously. Let's solve Equation 1 for \( x \): \[ x = 3y - 3 \] Now, substitute this expression for \( x \) into Equation 2: \[ 2(3y - 3) - 3y - 6 = 0 \] Expanding this gives: \[ 6y - 6 - 3y - 6 = 0 \] Combining like terms results in: \[ 3y - 12 = 0 \] Solving for \( y \): \[ 3y = 12 \quad \Rightarrow \quad y = 4 \] ### Step 5: Find \( x \) Now substitute \( y = 4 \) back into the expression for \( x \): \[ x = 3(4) - 3 = 12 - 3 = 9 \] ### Step 6: Calculate Total Number of Students The total number of students in the class is given by: \[ \text{Total Students} = x \times y = 9 \times 4 = 36 \] ### Final Answer The number of students in the class is **36**. ---
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