Finding the Third Proportional to 218,403 and 339,268.50

Step by Step Solution

1. Step 1: Write the proportion equation
   218,403 : 339,268.50 = 339,268.50 : x
2. Step 2: Convert to fraction form
   218,403/339,268.50 = 339,268.50/x
3. Step 3: Cross multiply
   218,403x = 339,268.50 × 339,268.50
4. Step 4: Simplify right side
   218,403x = 115,103,115,092.25
5. Step 5: Solve for x
   x = 115,103,115,092.25/218,403
6. Step 6: Final answer
   x = 527,021.68