Finding the Third Proportional to 4,431,589 and 9,639,638

Step by Step Solution

1. Step 1: Write the proportion equation
   4,431,589 : 9,639,638 = 9,639,638 : x
2. Step 2: Convert to fraction form
   4,431,589/9,639,638 = 9,639,638/x
3. Step 3: Cross multiply
   4,431,589x = 9,639,638 × 9,639,638
4. Step 4: Simplify right side
   4,431,589x = 92,922,620,771,044
5. Step 5: Solve for x
   x = 92,922,620,771,044/4,431,589
6. Step 6: Final answer
   x = 20,968,239.78