Finding the Third Proportional to 685,408.50 and 1,485,216

Step by Step Solution

1. Step 1: Write the proportion equation
   685,408.50 : 1,485,216 = 1,485,216 : x
2. Step 2: Convert to fraction form
   685,408.50/1,485,216 = 1,485,216/x
3. Step 3: Cross multiply
   685,408.50x = 1,485,216 × 1,485,216
4. Step 4: Simplify right side
   685,408.50x = 2,205,866,566,656
5. Step 5: Solve for x
   x = 2,205,866,566,656/685,408.50
6. Step 6: Final answer
   x = 3,218,323.91