Finding the Fourth Proportional to 8,086.56, 12,129.28 and 3,155.28

Step by Step Solution

1. Step 1: Write the proportion equation
   8,086.56 : 12,129.28 = 3,155.28 : x
2. Step 2: Convert to fraction form
   8,086.56/12,129.28 = 3,155.28/x
3. Step 3: Cross multiply
   8,086.56x = 12,129.28 × 3,155.28
4. Step 4: Simplify right side
   8,086.56x = 38,271,274.60
5. Step 5: Solve for x
   x = 38,271,274.60/8,086.56
6. Step 6: Final answer
   x = 4,732.70