Finding the Third Proportional to 685,840 and 1,485,728

Step by Step Solution

1. Step 1: Write the proportion equation
   685,840 : 1,485,728 = 1,485,728 : x
2. Step 2: Convert to fraction form
   685,840/1,485,728 = 1,485,728/x
3. Step 3: Cross multiply
   685,840x = 1,485,728 × 1,485,728
4. Step 4: Simplify right side
   685,840x = 2,207,387,689,984
5. Step 5: Solve for x
   x = 2,207,387,689,984/685,840
6. Step 6: Final answer
   x = 3,218,516.99