Finding the Third Proportional to 428,824 and 647,604

Step by Step Solution

1. Step 1: Write the proportion equation
   428,824 : 647,604 = 647,604 : x
2. Step 2: Convert to fraction form
   428,824/647,604 = 647,604/x
3. Step 3: Cross multiply
   428,824x = 647,604 × 647,604
4. Step 4: Simplify right side
   428,824x = 419,390,940,816
5. Step 5: Solve for x
   x = 419,390,940,816/428,824
6. Step 6: Final answer
   x = 978,002.49