Respuesta :
An expression is defined as a set of numbers, variables, and mathematical operations. There are a total of 10 benches in the class.
What is an Expression?
In mathematics, an expression is defined as a set of numbers, variables, and mathematical operations formed according to rules dependent on the context.
Let the total number of benches be represented by x. If students sit 3 per bench, we are short 3 benches. Therefore, the total number of students can be written as,
Total number of students = 3x + 9
If they sit 5 per bench, 2 benches are left empty, and one bench only has 4 students.
Total number of students = 5(x-1) - 10 +4
Now, the total number of students can be written as,
3x + 9 = 5(x-1) - 10 +4
3x + 9 = 5x - 11
20 = 2x
x = 10
Hence, there are a total of 10 benches in the class.
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