Finding the Fourth Proportional to 9,150.94, 12,628.58 and 5,172.31

Step by Step Solution

1. Step 1: Write the proportion equation
   9,150.94 : 12,628.58 = 5,172.31 : x
2. Step 2: Convert to fraction form
   9,150.94/12,628.58 = 5,172.31/x
3. Step 3: Cross multiply
   9,150.94x = 12,628.58 × 5,172.31
4. Step 4: Simplify right side
   9,150.94x = 65,318,930.62
5. Step 5: Solve for x
   x = 65,318,930.62/9,150.94
6. Step 6: Final answer
   x = 7,137.95