Finding the Third Proportional to 338,035.50 and 685,404

Step by Step Solution

1. Step 1: Write the proportion equation
   338,035.50 : 685,404 = 685,404 : x
2. Step 2: Convert to fraction form
   338,035.50/685,404 = 685,404/x
3. Step 3: Cross multiply
   338,035.50x = 685,404 × 685,404
4. Step 4: Simplify right side
   338,035.50x = 469,778,643,216
5. Step 5: Solve for x
   x = 469,778,643,216/338,035.50
6. Step 6: Final answer
   x = 1,389,731.68