Finding the Fourth Proportional to 9,151.98, 12,629.60 and 5,172.96

Step by Step Solution

1. Step 1: Write the proportion equation
   9,151.98 : 12,629.60 = 5,172.96 : x
2. Step 2: Convert to fraction form
   9,151.98/12,629.60 = 5,172.96/x
3. Step 3: Cross multiply
   9,151.98x = 12,629.60 × 5,172.96
4. Step 4: Simplify right side
   9,151.98x = 65,332,415.62
5. Step 5: Solve for x
   x = 65,332,415.62/9,151.98
6. Step 6: Final answer
   x = 7,138.61