Finding the Third Proportional to 3,940,687 and 8,489,278

Step by Step Solution

1. Step 1: Write the proportion equation
   3,940,687 : 8,489,278 = 8,489,278 : x
2. Step 2: Convert to fraction form
   3,940,687/8,489,278 = 8,489,278/x
3. Step 3: Cross multiply
   3,940,687x = 8,489,278 × 8,489,278
4. Step 4: Simplify right side
   3,940,687x = 72,067,840,961,284
5. Step 5: Solve for x
   x = 72,067,840,961,284/3,940,687
6. Step 6: Final answer
   x = 18,288,141.37