Finding the Fourth Proportional to 8,478.77, 12,718.56 and 4,099.91

Step by Step Solution

1. Step 1: Write the proportion equation
   8,478.77 : 12,718.56 = 4,099.91 : x
2. Step 2: Convert to fraction form
   8,478.77/12,718.56 = 4,099.91/x
3. Step 3: Cross multiply
   8,478.77x = 12,718.56 × 4,099.91
4. Step 4: Simplify right side
   8,478.77x = 52,144,951.33
5. Step 5: Solve for x
   x = 52,144,951.33/8,478.77
6. Step 6: Final answer
   x = 6,150.06