Finding the Third Proportional to 443,139 and 687,470

Step by Step Solution

1. Step 1: Write the proportion equation
   443,139 : 687,470 = 687,470 : x
2. Step 2: Convert to fraction form
   443,139/687,470 = 687,470/x
3. Step 3: Cross multiply
   443,139x = 687,470 × 687,470
4. Step 4: Simplify right side
   443,139x = 472,615,000,900
5. Step 5: Solve for x
   x = 472,615,000,900/443,139
6. Step 6: Final answer
   x = 1,066,516.38