Finding the Fourth Proportional to 9,158.54, 12,639.31 and 5,180.02

Step by Step Solution

1. Step 1: Write the proportion equation
   9,158.54 : 12,639.31 = 5,180.02 : x
2. Step 2: Convert to fraction form
   9,158.54/12,639.31 = 5,180.02/x
3. Step 3: Cross multiply
   9,158.54x = 12,639.31 × 5,180.02
4. Step 4: Simplify right side
   9,158.54x = 65,471,834.04
5. Step 5: Solve for x
   x = 65,471,834.04/9,158.54
6. Step 6: Final answer
   x = 7,148.72