Finding the Third Proportional to 309,639 and 472,462.50

Step by Step Solution

1. Step 1: Write the proportion equation
   309,639 : 472,462.50 = 472,462.50 : x
2. Step 2: Convert to fraction form
   309,639/472,462.50 = 472,462.50/x
3. Step 3: Cross multiply
   309,639x = 472,462.50 × 472,462.50
4. Step 4: Simplify right side
   309,639x = 223,220,813,906.25
5. Step 5: Solve for x
   x = 223,220,813,906.25/309,639
6. Step 6: Final answer
   x = 720,906.65