Finding the Third Proportional to 408,258 and 818,158.50

Step by Step Solution

1. Step 1: Write the proportion equation
   408,258 : 818,158.50 = 818,158.50 : x
2. Step 2: Convert to fraction form
   408,258/818,158.50 = 818,158.50/x
3. Step 3: Cross multiply
   408,258x = 818,158.50 × 818,158.50
4. Step 4: Simplify right side
   408,258x = 669,383,331,122.25
5. Step 5: Solve for x
   x = 669,383,331,122.25/408,258
6. Step 6: Final answer
   x = 1,639,608.61