Finding the Third Proportional to 487,620 and 647,011.50

Step by Step Solution

1. Step 1: Write the proportion equation
   487,620 : 647,011.50 = 647,011.50 : x
2. Step 2: Convert to fraction form
   487,620/647,011.50 = 647,011.50/x
3. Step 3: Cross multiply
   487,620x = 647,011.50 × 647,011.50
4. Step 4: Simplify right side
   487,620x = 418,623,881,132.25
5. Step 5: Solve for x
   x = 418,623,881,132.25/487,620
6. Step 6: Final answer
   x = 858,504.33