Finding the Third Proportional to 299,623 and 641,892.50

Step by Step Solution

1. Step 1: Write the proportion equation
   299,623 : 641,892.50 = 641,892.50 : x
2. Step 2: Convert to fraction form
   299,623/641,892.50 = 641,892.50/x
3. Step 3: Cross multiply
   299,623x = 641,892.50 × 641,892.50
4. Step 4: Simplify right side
   299,623x = 412,025,981,556.25
5. Step 5: Solve for x
   x = 412,025,981,556.25/299,623
6. Step 6: Final answer
   x = 1,375,148.04