Finding the Third Proportional to 398,173.50 and 859,689

Step by Step Solution

1. Step 1: Write the proportion equation
   398,173.50 : 859,689 = 859,689 : x
2. Step 2: Convert to fraction form
   398,173.50/859,689 = 859,689/x
3. Step 3: Cross multiply
   398,173.50x = 859,689 × 859,689
4. Step 4: Simplify right side
   398,173.50x = 739,065,176,721
5. Step 5: Solve for x
   x = 739,065,176,721/398,173.50
6. Step 6: Final answer
   x = 1,856,138.53