Finding the Fourth Proportional to 12,139.78, 16,757.60 and 9,488.04

Step by Step Solution

1. Step 1: Write the proportion equation
   12,139.78 : 16,757.60 = 9,488.04 : x
2. Step 2: Convert to fraction form
   12,139.78/16,757.60 = 9,488.04/x
3. Step 3: Cross multiply
   12,139.78x = 16,757.60 × 9,488.04
4. Step 4: Simplify right side
   12,139.78x = 158,996,731.66
5. Step 5: Solve for x
   x = 158,996,731.66/12,139.78
6. Step 6: Final answer
   x = 13,097.17