Finding the Third Proportional to 287,620 and 619,384

Step by Step Solution

1. Step 1: Write the proportion equation
   287,620 : 619,384 = 619,384 : x
2. Step 2: Convert to fraction form
   287,620/619,384 = 619,384/x
3. Step 3: Cross multiply
   287,620x = 619,384 × 619,384
4. Step 4: Simplify right side
   287,620x = 383,636,539,456
5. Step 5: Solve for x
   x = 383,636,539,456/287,620
6. Step 6: Final answer
   x = 1,333,831.23