Finding the Third Proportional to 309,218 and 665,181.25

Step by Step Solution

1. Step 1: Write the proportion equation
   309,218 : 665,181.25 = 665,181.25 : x
2. Step 2: Convert to fraction form
   309,218/665,181.25 = 665,181.25/x
3. Step 3: Cross multiply
   309,218x = 665,181.25 × 665,181.25
4. Step 4: Simplify right side
   309,218x = 442,466,095,351.56
5. Step 5: Solve for x
   x = 442,466,095,351.56/309,218
6. Step 6: Final answer
   x = 1,430,919.60