Finding the Third Proportional to 357,129 and 485,023.50

Step by Step Solution

1. Step 1: Write the proportion equation
   357,129 : 485,023.50 = 485,023.50 : x
2. Step 2: Convert to fraction form
   357,129/485,023.50 = 485,023.50/x
3. Step 3: Cross multiply
   357,129x = 485,023.50 × 485,023.50
4. Step 4: Simplify right side
   357,129x = 235,247,795,552.25
5. Step 5: Solve for x
   x = 235,247,795,552.25/357,129
6. Step 6: Final answer
   x = 658,719.39