Finding the Third Proportional to 3,980,328 and 8,636,439

Step by Step Solution

1. Step 1: Write the proportion equation
   3,980,328 : 8,636,439 = 8,636,439 : x
2. Step 2: Convert to fraction form
   3,980,328/8,636,439 = 8,636,439/x
3. Step 3: Cross multiply
   3,980,328x = 8,636,439 × 8,636,439
4. Step 4: Simplify right side
   3,980,328x = 74,588,078,600,721
5. Step 5: Solve for x
   x = 74,588,078,600,721/3,980,328
6. Step 6: Final answer
   x = 18,739,178.93