Finding the Third Proportional to 280,513 and 394,561.50

Step by Step Solution

1. Step 1: Write the proportion equation
   280,513 : 394,561.50 = 394,561.50 : x
2. Step 2: Convert to fraction form
   280,513/394,561.50 = 394,561.50/x
3. Step 3: Cross multiply
   280,513x = 394,561.50 × 394,561.50
4. Step 4: Simplify right side
   280,513x = 155,678,777,282.25
5. Step 5: Solve for x
   x = 155,678,777,282.25/280,513
6. Step 6: Final answer
   x = 554,978.83