Finding the Fourth Proportional to 12,499.83, 18,617.13 and 12,439.50

Step by Step Solution

1. Step 1: Write the proportion equation
   12,499.83 : 18,617.13 = 12,439.50 : x
2. Step 2: Convert to fraction form
   12,499.83/18,617.13 = 12,439.50/x
3. Step 3: Cross multiply
   12,499.83x = 18,617.13 × 12,439.50
4. Step 4: Simplify right side
   12,499.83x = 231,587,788.64
5. Step 5: Solve for x
   x = 231,587,788.64/12,499.83
6. Step 6: Final answer
   x = 18,527.28