Finding the Fourth Proportional to 12,108.90, 18,165.36 and 3,789.72

Step by Step Solution

1. Step 1: Write the proportion equation
   12,108.90 : 18,165.36 = 3,789.72 : x
2. Step 2: Convert to fraction form
   12,108.90/18,165.36 = 3,789.72/x
3. Step 3: Cross multiply
   12,108.90x = 18,165.36 × 3,789.72
4. Step 4: Simplify right side
   12,108.90x = 68,841,628.10
5. Step 5: Solve for x
   x = 68,841,628.10/12,108.90
6. Step 6: Final answer
   x = 5,685.21