Finding the Third Proportional to 259,898 and 388,789

Step by Step Solution

1. Step 1: Write the proportion equation
   259,898 : 388,789 = 388,789 : x
2. Step 2: Convert to fraction form
   259,898/388,789 = 388,789/x
3. Step 3: Cross multiply
   259,898x = 388,789 × 388,789
4. Step 4: Simplify right side
   259,898x = 151,156,886,521
5. Step 5: Solve for x
   x = 151,156,886,521/259,898
6. Step 6: Final answer
   x = 581,600.81