Finding the Third Proportional to 9,920,556 and 21,258,288

Step by Step Solution

1. Step 1: Write the proportion equation
   9,920,556 : 21,258,288 = 21,258,288 : x
2. Step 2: Convert to fraction form
   9,920,556/21,258,288 = 21,258,288/x
3. Step 3: Cross multiply
   9,920,556x = 21,258,288 × 21,258,288
4. Step 4: Simplify right side
   9,920,556x = 451,914,808,690,944
5. Step 5: Solve for x
   x = 451,914,808,690,944/9,920,556
6. Step 6: Final answer
   x = 45,553,375.10