Finding the Third Proportional to 381,665.50 and 518,339.50

Step by Step Solution

1. Step 1: Write the proportion equation
   381,665.50 : 518,339.50 = 518,339.50 : x
2. Step 2: Convert to fraction form
   381,665.50/518,339.50 = 518,339.50/x
3. Step 3: Cross multiply
   381,665.50x = 518,339.50 × 518,339.50
4. Step 4: Simplify right side
   381,665.50x = 268,675,837,260.25
5. Step 5: Solve for x
   x = 268,675,837,260.25/381,665.50
6. Step 6: Final answer
   x = 703,956.31