Finding the Fourth Proportional to 9,137.78, 12,609.42 and 5,159.28

Step by Step Solution

1. Step 1: Write the proportion equation
   9,137.78 : 12,609.42 = 5,159.28 : x
2. Step 2: Convert to fraction form
   9,137.78/12,609.42 = 5,159.28/x
3. Step 3: Cross multiply
   9,137.78x = 12,609.42 × 5,159.28
4. Step 4: Simplify right side
   9,137.78x = 65,055,541.32
5. Step 5: Solve for x
   x = 65,055,541.32/9,137.78
6. Step 6: Final answer
   x = 7,119.41