Finding the Third Proportional to 198,686 and 425,780.50

Step by Step Solution

1. Step 1: Write the proportion equation
   198,686 : 425,780.50 = 425,780.50 : x
2. Step 2: Convert to fraction form
   198,686/425,780.50 = 425,780.50/x
3. Step 3: Cross multiply
   198,686x = 425,780.50 × 425,780.50
4. Step 4: Simplify right side
   198,686x = 181,289,034,180.25
5. Step 5: Solve for x
   x = 181,289,034,180.25/198,686
6. Step 6: Final answer
   x = 912,439.90