9+9:9+9•9-9

To solve the expression \( 9 + 9 : 9 + 9 \cdot 9 - 9 \), we will follow the order of operations, often remembered by the acronym PEMDAS (Parentheses, Exponents, Multiplication and Division (from left to right), Addition and Subtraction (from left to right)).

Let's break it down step by step:

1. Identify operations:

   • Addition: \( + \)
   • Subtraction: \( - \)
   • Multiplication: \( \cdot \)
   • Division: \( : \) (which means the same as \( / \))

2. Rewrite the expression using standard symbols: \( 9 + 9 / 9 + 9 \cdot 9 - 9 \)

3. Evaluate the division and multiplication first:

   • \( 9 / 9 = 1 \)
   • \( 9 \cdot 9 = 81 \)

   Now we can rewrite the expression: \[ 9 + 1 + 81 - 9 \]

4. Perform the addition and subtraction from left to right:

   • \( 9 + 1 = 10 \)
   • \( 10 + 81 = 91 \)
   • \( 91 - 9 = 82 \)

So, the final result is \( 82 \).