Finding the Third Proportional to 4,222.69 and 8,722.69

Step by Step Solution

1. Step 1: Write the proportion equation
   4,222.69 : 8,722.69 = 8,722.69 : x
2. Step 2: Convert to fraction form
   4,222.69/8,722.69 = 8,722.69/x
3. Step 3: Cross multiply
   4,222.69x = 8,722.69 × 8,722.69
4. Step 4: Simplify right side
   4,222.69x = 76,085,277.22
5. Step 5: Solve for x
   x = 76,085,277.22/4,222.69
6. Step 6: Final answer
   x = 18,018.21