Finding the Fourth Proportional to 9,406.36, 12,978.20 and 5,819.60

Step by Step Solution

1. Step 1: Write the proportion equation
   9,406.36 : 12,978.20 = 5,819.60 : x
2. Step 2: Convert to fraction form
   9,406.36/12,978.20 = 5,819.60/x
3. Step 3: Cross multiply
   9,406.36x = 12,978.20 × 5,819.60
4. Step 4: Simplify right side
   9,406.36x = 75,527,878.45
5. Step 5: Solve for x
   x = 75,527,878.45/9,406.36
6. Step 6: Final answer
   x = 8,029.45