Finding the Third Proportional to 298,685 and 644,914

Step by Step Solution

1. Step 1: Write the proportion equation
   298,685 : 644,914 = 644,914 : x
2. Step 2: Convert to fraction form
   298,685/644,914 = 644,914/x
3. Step 3: Cross multiply
   298,685x = 644,914 × 644,914
4. Step 4: Simplify right side
   298,685x = 415,914,067,396
5. Step 5: Solve for x
   x = 415,914,067,396/298,685
6. Step 6: Final answer
   x = 1,392,483.95