Finding the Third Proportional to 399,499.75 and 858,291.25

Step by Step Solution

1. Step 1: Write the proportion equation
   399,499.75 : 858,291.25 = 858,291.25 : x
2. Step 2: Convert to fraction form
   399,499.75/858,291.25 = 858,291.25/x
3. Step 3: Cross multiply
   399,499.75x = 858,291.25 × 858,291.25
4. Step 4: Simplify right side
   399,499.75x = 736,663,869,826.56
5. Step 5: Solve for x
   x = 736,663,869,826.56/399,499.75
6. Step 6: Final answer
   x = 1,843,965.78