Finding the Third Proportional to 3,940,684 and 8,489,272

Step by Step Solution

1. Step 1: Write the proportion equation
   3,940,684 : 8,489,272 = 8,489,272 : x
2. Step 2: Convert to fraction form
   3,940,684/8,489,272 = 8,489,272/x
3. Step 3: Cross multiply
   3,940,684x = 8,489,272 × 8,489,272
4. Step 4: Simplify right side
   3,940,684x = 72,067,739,089,984
5. Step 5: Solve for x
   x = 72,067,739,089,984/3,940,684
6. Step 6: Final answer
   x = 18,288,129.44