Finding the Third Proportional to 3,578,858 and 5,420,409

Step by Step Solution

1. Step 1: Write the proportion equation
   3,578,858 : 5,420,409 = 5,420,409 : x
2. Step 2: Convert to fraction form
   3,578,858/5,420,409 = 5,420,409/x
3. Step 3: Cross multiply
   3,578,858x = 5,420,409 × 5,420,409
4. Step 4: Simplify right side
   3,578,858x = 29,380,833,727,281
5. Step 5: Solve for x
   x = 29,380,833,727,281/3,578,858
6. Step 6: Final answer
   x = 8,209,555.60