Finding the Fourth Proportional to 9,151.40, 12,629.18 and 5,172.42

Step by Step Solution

1. Step 1: Write the proportion equation
   9,151.40 : 12,629.18 = 5,172.42 : x
2. Step 2: Convert to fraction form
   9,151.40/12,629.18 = 5,172.42/x
3. Step 3: Cross multiply
   9,151.40x = 12,629.18 × 5,172.42
4. Step 4: Simplify right side
   9,151.40x = 65,323,397.35
5. Step 5: Solve for x
   x = 65,323,397.35/9,151.40
6. Step 6: Final answer
   x = 7,138.08