Finding the Third Proportional to 185,139 and 398,406

Step by Step Solution

1. Step 1: Write the proportion equation
   185,139 : 398,406 = 398,406 : x
2. Step 2: Convert to fraction form
   185,139/398,406 = 398,406/x
3. Step 3: Cross multiply
   185,139x = 398,406 × 398,406
4. Step 4: Simplify right side
   185,139x = 158,727,340,836
5. Step 5: Solve for x
   x = 158,727,340,836/185,139
6. Step 6: Final answer
   x = 857,341.46