Finding the Fourth Proportional to 8,978.36, 12,390.72 and 6,179

Step by Step Solution

1. Step 1: Write the proportion equation
   8,978.36 : 12,390.72 = 6,179 : x
2. Step 2: Convert to fraction form
   8,978.36/12,390.72 = 6,179/x
3. Step 3: Cross multiply
   8,978.36x = 12,390.72 × 6,179
4. Step 4: Simplify right side
   8,978.36x = 76,562,258.88
5. Step 5: Solve for x
   x = 76,562,258.88/8,978.36
6. Step 6: Final answer
   x = 8,527.42