Finding the Fourth Proportional to 12,128.68, 18,179.25 and 5,470.63

Step by Step Solution

1. Step 1: Write the proportion equation
   12,128.68 : 18,179.25 = 5,470.63 : x
2. Step 2: Convert to fraction form
   12,128.68/18,179.25 = 5,470.63/x
3. Step 3: Cross multiply
   12,128.68x = 18,179.25 × 5,470.63
4. Step 4: Simplify right side
   12,128.68x = 99,451,950.43
5. Step 5: Solve for x
   x = 99,451,950.43/12,128.68
6. Step 6: Final answer
   x = 8,199.73