Finding the Third Proportional to 120,399 and 263,635.50

Step by Step Solution

1. Step 1: Write the proportion equation
   120,399 : 263,635.50 = 263,635.50 : x
2. Step 2: Convert to fraction form
   120,399/263,635.50 = 263,635.50/x
3. Step 3: Cross multiply
   120,399x = 263,635.50 × 263,635.50
4. Step 4: Simplify right side
   120,399x = 69,503,676,860.25
5. Step 5: Solve for x
   x = 69,503,676,860.25/120,399
6. Step 6: Final answer
   x = 577,277.86