Finding the Third Proportional to 397,939.50 and 819,207

Step by Step Solution

1. Step 1: Write the proportion equation
   397,939.50 : 819,207 = 819,207 : x
2. Step 2: Convert to fraction form
   397,939.50/819,207 = 819,207/x
3. Step 3: Cross multiply
   397,939.50x = 819,207 × 819,207
4. Step 4: Simplify right side
   397,939.50x = 671,100,108,849
5. Step 5: Solve for x
   x = 671,100,108,849/397,939.50
6. Step 6: Final answer
   x = 1,686,437.53