Finding the Third Proportional to 309,671 and 478,601.50

Step by Step Solution

1. Step 1: Write the proportion equation
   309,671 : 478,601.50 = 478,601.50 : x
2. Step 2: Convert to fraction form
   309,671/478,601.50 = 478,601.50/x
3. Step 3: Cross multiply
   309,671x = 478,601.50 × 478,601.50
4. Step 4: Simplify right side
   309,671x = 229,059,395,802.25
5. Step 5: Solve for x
   x = 229,059,395,802.25/309,671
6. Step 6: Final answer
   x = 739,686.30