Finding the Fourth Proportional to 9,159.72, 12,639.88 and 5,180.60

Step by Step Solution

1. Step 1: Write the proportion equation
   9,159.72 : 12,639.88 = 5,180.60 : x
2. Step 2: Convert to fraction form
   9,159.72/12,639.88 = 5,180.60/x
3. Step 3: Cross multiply
   9,159.72x = 12,639.88 × 5,180.60
4. Step 4: Simplify right side
   9,159.72x = 65,482,162.33
5. Step 5: Solve for x
   x = 65,482,162.33/9,159.72
6. Step 6: Final answer
   x = 7,148.93