Finding the Third Proportional to 120,616 and 257,831.50

Step by Step Solution

1. Step 1: Write the proportion equation
   120,616 : 257,831.50 = 257,831.50 : x
2. Step 2: Convert to fraction form
   120,616/257,831.50 = 257,831.50/x
3. Step 3: Cross multiply
   120,616x = 257,831.50 × 257,831.50
4. Step 4: Simplify right side
   120,616x = 66,477,082,392.25
5. Step 5: Solve for x
   x = 66,477,082,392.25/120,616
6. Step 6: Final answer
   x = 551,146.47