Finding the Third Proportional to 400,413 and 539,329.50

Step by Step Solution

1. Step 1: Write the proportion equation
   400,413 : 539,329.50 = 539,329.50 : x
2. Step 2: Convert to fraction form
   400,413/539,329.50 = 539,329.50/x
3. Step 3: Cross multiply
   400,413x = 539,329.50 × 539,329.50
4. Step 4: Simplify right side
   400,413x = 290,876,309,570.25
5. Step 5: Solve for x
   x = 290,876,309,570.25/400,413
6. Step 6: Final answer
   x = 726,440.72