Finding the Third Proportional to 309,651.75 and 647,392.50

Step by Step Solution

1. Step 1: Write the proportion equation
   309,651.75 : 647,392.50 = 647,392.50 : x
2. Step 2: Convert to fraction form
   309,651.75/647,392.50 = 647,392.50/x
3. Step 3: Cross multiply
   309,651.75x = 647,392.50 × 647,392.50
4. Step 4: Simplify right side
   309,651.75x = 419,117,049,056.25
5. Step 5: Solve for x
   x = 419,117,049,056.25/309,651.75
6. Step 6: Final answer
   x = 1,353,511.00