Finding the Third Proportional to 389,649 and 839,490

Step by Step Solution

1. Step 1: Write the proportion equation
   389,649 : 839,490 = 839,490 : x
2. Step 2: Convert to fraction form
   389,649/839,490 = 839,490/x
3. Step 3: Cross multiply
   389,649x = 839,490 × 839,490
4. Step 4: Simplify right side
   389,649x = 704,743,460,100
5. Step 5: Solve for x
   x = 704,743,460,100/389,649
6. Step 6: Final answer
   x = 1,808,662.31