Finding the Fourth Proportional to 8,479.38, 12,647.00 and 8,331.78

Step by Step Solution

1. Step 1: Write the proportion equation
   8,479.38 : 12,647.00 = 8,331.78 : x
2. Step 2: Convert to fraction form
   8,479.38/12,647.00 = 8,331.78/x
3. Step 3: Cross multiply
   8,479.38x = 12,647.00 × 8,331.78
4. Step 4: Simplify right side
   8,479.38x = 105,371,980.00
5. Step 5: Solve for x
   x = 105,371,980.00/8,479.38
6. Step 6: Final answer
   x = 12,426.85