Finding the Fourth Proportional to 8,676.72, 13,007.22 and 3,128.76

Step by Step Solution

1. Step 1: Write the proportion equation
   8,676.72 : 13,007.22 = 3,128.76 : x
2. Step 2: Convert to fraction form
   8,676.72/13,007.22 = 3,128.76/x
3. Step 3: Cross multiply
   8,676.72x = 13,007.22 × 3,128.76
4. Step 4: Simplify right side
   8,676.72x = 40,696,469.65
5. Step 5: Solve for x
   x = 40,696,469.65/8,676.72
6. Step 6: Final answer
   x = 4,690.31