Finding the Third Proportional to 518,389.50 and 811,443.50

Step by Step Solution

1. Step 1: Write the proportion equation
   518,389.50 : 811,443.50 = 811,443.50 : x
2. Step 2: Convert to fraction form
   518,389.50/811,443.50 = 811,443.50/x
3. Step 3: Cross multiply
   518,389.50x = 811,443.50 × 811,443.50
4. Step 4: Simplify right side
   518,389.50x = 658,440,553,692.25
5. Step 5: Solve for x
   x = 658,440,553,692.25/518,389.50
6. Step 6: Final answer
   x = 1,270,165.68