Finding the Third Proportional to 258,606 and 397,399.50

Step by Step Solution

1. Step 1: Write the proportion equation
   258,606 : 397,399.50 = 397,399.50 : x
2. Step 2: Convert to fraction form
   258,606/397,399.50 = 397,399.50/x
3. Step 3: Cross multiply
   258,606x = 397,399.50 × 397,399.50
4. Step 4: Simplify right side
   258,606x = 157,926,362,600.25
5. Step 5: Solve for x
   x = 157,926,362,600.25/258,606
6. Step 6: Final answer
   x = 610,683.29