Finding the Third Proportional to 331,411 and 518,443

Step by Step Solution

1. Step 1: Write the proportion equation
   331,411 : 518,443 = 518,443 : x
2. Step 2: Convert to fraction form
   331,411/518,443 = 518,443/x
3. Step 3: Cross multiply
   331,411x = 518,443 × 518,443
4. Step 4: Simplify right side
   331,411x = 268,783,144,249
5. Step 5: Solve for x
   x = 268,783,144,249/331,411
6. Step 6: Final answer
   x = 811,026.62