Finding the Third Proportional to 259,911 and 558,499.50

Step by Step Solution

1. Step 1: Write the proportion equation
   259,911 : 558,499.50 = 558,499.50 : x
2. Step 2: Convert to fraction form
   259,911/558,499.50 = 558,499.50/x
3. Step 3: Cross multiply
   259,911x = 558,499.50 × 558,499.50
4. Step 4: Simplify right side
   259,911x = 311,921,691,500.25
5. Step 5: Solve for x
   x = 311,921,691,500.25/259,911
6. Step 6: Final answer
   x = 1,200,109.62