Finding the Third Proportional to 275,436 and 389,913

Step by Step Solution

1. Step 1: Write the proportion equation
   275,436 : 389,913 = 389,913 : x
2. Step 2: Convert to fraction form
   275,436/389,913 = 389,913/x
3. Step 3: Cross multiply
   275,436x = 389,913 × 389,913
4. Step 4: Simplify right side
   275,436x = 152,032,147,569
5. Step 5: Solve for x
   x = 152,032,147,569/275,436
6. Step 6: Final answer
   x = 551,969.05