Finding the Third Proportional to 309,914 and 478,540

Step by Step Solution

1. Step 1: Write the proportion equation
   309,914 : 478,540 = 478,540 : x
2. Step 2: Convert to fraction form
   309,914/478,540 = 478,540/x
3. Step 3: Cross multiply
   309,914x = 478,540 × 478,540
4. Step 4: Simplify right side
   309,914x = 229,000,531,600
5. Step 5: Solve for x
   x = 229,000,531,600/309,914
6. Step 6: Final answer
   x = 738,916.38