Finding the Third Proportional to 309,948 and 478,740

Step by Step Solution

1. Step 1: Write the proportion equation
   309,948 : 478,740 = 478,740 : x
2. Step 2: Convert to fraction form
   309,948/478,740 = 478,740/x
3. Step 3: Cross multiply
   309,948x = 478,740 × 478,740
4. Step 4: Simplify right side
   309,948x = 229,191,987,600
5. Step 5: Solve for x
   x = 229,191,987,600/309,948
6. Step 6: Final answer
   x = 739,453.03