Finding the Third Proportional to 639,730.69 and 1,378,605.38

Step by Step Solution

1. Step 1: Write the proportion equation
   639,730.69 : 1,378,605.38 = 1,378,605.38 : x
2. Step 2: Convert to fraction form
   639,730.69/1,378,605.38 = 1,378,605.38/x
3. Step 3: Cross multiply
   639,730.69x = 1,378,605.38 × 1,378,605.38
4. Step 4: Simplify right side
   639,730.69x = 1,900,552,779,978.89
5. Step 5: Solve for x
   x = 1,900,552,779,978.89/639,730.69
6. Step 6: Final answer
   x = 2,970,863.86