Finding the Third Proportional to 381,705.50 and 518,399.50

Step by Step Solution

1. Step 1: Write the proportion equation
   381,705.50 : 518,399.50 = 518,399.50 : x
2. Step 2: Convert to fraction form
   381,705.50/518,399.50 = 518,399.50/x
3. Step 3: Cross multiply
   381,705.50x = 518,399.50 × 518,399.50
4. Step 4: Simplify right side
   381,705.50x = 268,738,041,600.25
5. Step 5: Solve for x
   x = 268,738,041,600.25/381,705.50
6. Step 6: Final answer
   x = 704,045.51