Finding the Third Proportional to 3,987,878 and 8,648,812

Step by Step Solution

1. Step 1: Write the proportion equation
   3,987,878 : 8,648,812 = 8,648,812 : x
2. Step 2: Convert to fraction form
   3,987,878/8,648,812 = 8,648,812/x
3. Step 3: Cross multiply
   3,987,878x = 8,648,812 × 8,648,812
4. Step 4: Simplify right side
   3,987,878x = 74,801,949,011,344
5. Step 5: Solve for x
   x = 74,801,949,011,344/3,987,878
6. Step 6: Final answer
   x = 18,757,331.35