Finding the Third Proportional to 3,987,866 and 8,648,788

Step by Step Solution

1. Step 1: Write the proportion equation
   3,987,866 : 8,648,788 = 8,648,788 : x
2. Step 2: Convert to fraction form
   3,987,866/8,648,788 = 8,648,788/x
3. Step 3: Cross multiply
   3,987,866x = 8,648,788 × 8,648,788
4. Step 4: Simplify right side
   3,987,866x = 74,801,533,868,944
5. Step 5: Solve for x
   x = 74,801,533,868,944/3,987,866
6. Step 6: Final answer
   x = 18,757,283.69