Finding the Fourth Proportional to 12,128.69, 16,738.55 and 6,823.90

Step by Step Solution

1. Step 1: Write the proportion equation
   12,128.69 : 16,738.55 = 6,823.90 : x
2. Step 2: Convert to fraction form
   12,128.69/16,738.55 = 6,823.90/x
3. Step 3: Cross multiply
   12,128.69x = 16,738.55 × 6,823.90
4. Step 4: Simplify right side
   12,128.69x = 114,222,191.35
5. Step 5: Solve for x
   x = 114,222,191.35/12,128.69
6. Step 6: Final answer
   x = 9,417.52