Finding the Third Proportional to 4,039,719 and 8,639,311

Step by Step Solution

1. Step 1: Write the proportion equation
   4,039,719 : 8,639,311 = 8,639,311 : x
2. Step 2: Convert to fraction form
   4,039,719/8,639,311 = 8,639,311/x
3. Step 3: Cross multiply
   4,039,719x = 8,639,311 × 8,639,311
4. Step 4: Simplify right side
   4,039,719x = 74,637,694,554,721
5. Step 5: Solve for x
   x = 74,637,694,554,721/4,039,719
6. Step 6: Final answer
   x = 18,475,961.96