Mathematical expressions are a combination of numbers, variables (like x, y, or z), and operators (like +, −, ×, and ÷) that represent a particular value or quantity. For example, 2+3 is a simple mathematical expression. The + is an operator that tells us to add the two numbers together.

Division is one of the four basic operations in arithmetic, along with addition, subtraction, and multiplication. When you divide one number by another, you're essentially asking "how many times does the second number fit into the first number?"

In the case of 100÷4, you're asking "how many times does 4 fit into 100?"

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