Finding the Third Proportional to 203,989.50 and 315,499.50

Step by Step Solution

1. Step 1: Write the proportion equation
   203,989.50 : 315,499.50 = 315,499.50 : x
2. Step 2: Convert to fraction form
   203,989.50/315,499.50 = 315,499.50/x
3. Step 3: Cross multiply
   203,989.50x = 315,499.50 × 315,499.50
4. Step 4: Simplify right side
   203,989.50x = 99,539,934,500.25
5. Step 5: Solve for x
   x = 99,539,934,500.25/203,989.50
6. Step 6: Final answer
   x = 487,965.97