Finding the Third Proportional to 259,907 and 391,780.50

Step by Step Solution

1. Step 1: Write the proportion equation
   259,907 : 391,780.50 = 391,780.50 : x
2. Step 2: Convert to fraction form
   259,907/391,780.50 = 391,780.50/x
3. Step 3: Cross multiply
   259,907x = 391,780.50 × 391,780.50
4. Step 4: Simplify right side
   259,907x = 153,491,960,180.25
5. Step 5: Solve for x
   x = 153,491,960,180.25/259,907
6. Step 6: Final answer
   x = 590,564.93