Finding the Third Proportional to 356,490 and 518,683.50

Step by Step Solution

1. Step 1: Write the proportion equation
   356,490 : 518,683.50 = 518,683.50 : x
2. Step 2: Convert to fraction form
   356,490/518,683.50 = 518,683.50/x
3. Step 3: Cross multiply
   356,490x = 518,683.50 × 518,683.50
4. Step 4: Simplify right side
   356,490x = 269,032,573,172.25
5. Step 5: Solve for x
   x = 269,032,573,172.25/356,490
6. Step 6: Final answer
   x = 754,670.74