Finding the Fourth Proportional to 3,128.76, 4,691.16 and 2,664.72

Step by Step Solution

1. Step 1: Write the proportion equation
   3,128.76 : 4,691.16 = 2,664.72 : x
2. Step 2: Convert to fraction form
   3,128.76/4,691.16 = 2,664.72/x
3. Step 3: Cross multiply
   3,128.76x = 4,691.16 × 2,664.72
4. Step 4: Simplify right side
   3,128.76x = 12,500,627.88
5. Step 5: Solve for x
   x = 12,500,627.88/3,128.76
6. Step 6: Final answer
   x = 3,995.39