Finding the Third Proportional to 321,570 and 685,856

Step by Step Solution

1. Step 1: Write the proportion equation
   321,570 : 685,856 = 685,856 : x
2. Step 2: Convert to fraction form
   321,570/685,856 = 685,856/x
3. Step 3: Cross multiply
   321,570x = 685,856 × 685,856
4. Step 4: Simplify right side
   321,570x = 470,398,452,736
5. Step 5: Solve for x
   x = 470,398,452,736/321,570
6. Step 6: Final answer
   x = 1,462,818.21