Finding the Fourth Proportional to 9,159.35, 12,639.93 and 5,180.72

Step by Step Solution

1. Step 1: Write the proportion equation
   9,159.35 : 12,639.93 = 5,180.72 : x
2. Step 2: Convert to fraction form
   9,159.35/12,639.93 = 5,180.72/x
3. Step 3: Cross multiply
   9,159.35x = 12,639.93 × 5,180.72
4. Step 4: Simplify right side
   9,159.35x = 65,483,938.15
5. Step 5: Solve for x
   x = 65,483,938.15/9,159.35
6. Step 6: Final answer
   x = 7,149.41