Finding the Third Proportional to 198,558 and 387,085.50

Step by Step Solution

1. Step 1: Write the proportion equation
   198,558 : 387,085.50 = 387,085.50 : x
2. Step 2: Convert to fraction form
   198,558/387,085.50 = 387,085.50/x
3. Step 3: Cross multiply
   198,558x = 387,085.50 × 387,085.50
4. Step 4: Simplify right side
   198,558x = 149,835,184,310.25
5. Step 5: Solve for x
   x = 149,835,184,310.25/198,558
6. Step 6: Final answer
   x = 754,616.71