Solve the Division Equation: Finding the Number That Equals 19 When Divided By 1

To solve this problem, we'll follow these steps:

• Step 1: Recognize the type of operation: division by 1.
• Step 2: Apply the property of division which states that dividing any number by 1 results in the number itself.
• Step 3: Identify the unknown value that satisfies the equation using this property.

Now, let's work through each step:
Step 1: The problem is represented as $?:1 = 19$. We need to determine the missing number that satisfies this equation.
Step 2: Recall the fundamental property of division: for any number $x$, $x \div 1 = x$. Thus, the number divided by 1 is equal to the number itself.
Step 3: To satisfy the equation $?:1 = 19$, the unknown value must be the number 19 itself because dividing 19 by 1 gives 19.

Therefore, the solution to the problem is 19.