Finding the Third Proportional to 3,945,411 and 8,621,280

Step by Step Solution

1. Step 1: Write the proportion equation
   3,945,411 : 8,621,280 = 8,621,280 : x
2. Step 2: Convert to fraction form
   3,945,411/8,621,280 = 8,621,280/x
3. Step 3: Cross multiply
   3,945,411x = 8,621,280 × 8,621,280
4. Step 4: Simplify right side
   3,945,411x = 74,326,468,838,400
5. Step 5: Solve for x
   x = 74,326,468,838,400/3,945,411
6. Step 6: Final answer
   x = 18,838,713.85