Finding the Third Proportional to 331,422 and 518,458.50

Step by Step Solution

1. Step 1: Write the proportion equation
   331,422 : 518,458.50 = 518,458.50 : x
2. Step 2: Convert to fraction form
   331,422/518,458.50 = 518,458.50/x
3. Step 3: Cross multiply
   331,422x = 518,458.50 × 518,458.50
4. Step 4: Simplify right side
   331,422x = 268,799,216,222.25
5. Step 5: Solve for x
   x = 268,799,216,222.25/331,422
6. Step 6: Final answer
   x = 811,048.20