Finding the Third Proportional to 639,612 and 1,408,008

Step by Step Solution

1. Step 1: Write the proportion equation
   639,612 : 1,408,008 = 1,408,008 : x
2. Step 2: Convert to fraction form
   639,612/1,408,008 = 1,408,008/x
3. Step 3: Cross multiply
   639,612x = 1,408,008 × 1,408,008
4. Step 4: Simplify right side
   639,612x = 1,982,486,528,064
5. Step 5: Solve for x
   x = 1,982,486,528,064/639,612
6. Step 6: Final answer
   x = 3,099,514.28