Finding the Third Proportional to 3,899,518 and 8,415,584

Step by Step Solution

1. Step 1: Write the proportion equation
   3,899,518 : 8,415,584 = 8,415,584 : x
2. Step 2: Convert to fraction form
   3,899,518/8,415,584 = 8,415,584/x
3. Step 3: Cross multiply
   3,899,518x = 8,415,584 × 8,415,584
4. Step 4: Simplify right side
   3,899,518x = 70,822,054,061,056
5. Step 5: Solve for x
   x = 70,822,054,061,056/3,899,518
6. Step 6: Final answer
   x = 18,161,745.65