Finding the Third Proportional to 3,578,857 and 5,420,408

Step by Step Solution

1. Step 1: Write the proportion equation
   3,578,857 : 5,420,408 = 5,420,408 : x
2. Step 2: Convert to fraction form
   3,578,857/5,420,408 = 5,420,408/x
3. Step 3: Cross multiply
   3,578,857x = 5,420,408 × 5,420,408
4. Step 4: Simplify right side
   3,578,857x = 29,380,822,886,464
5. Step 5: Solve for x
   x = 29,380,822,886,464/3,578,857
6. Step 6: Final answer
   x = 8,209,554.86