Finding the Third Proportional to 3,940,814 and 8,470,921

Step by Step Solution

1. Step 1: Write the proportion equation
   3,940,814 : 8,470,921 = 8,470,921 : x
2. Step 2: Convert to fraction form
   3,940,814/8,470,921 = 8,470,921/x
3. Step 3: Cross multiply
   3,940,814x = 8,470,921 × 8,470,921
4. Step 4: Simplify right side
   3,940,814x = 71,756,502,588,241
5. Step 5: Solve for x
   x = 71,756,502,588,241/3,940,814
6. Step 6: Final answer
   x = 18,208,548.43