Finding the Fourth Proportional to 9,138.88, 12,610.38 and 5,159.80

Step by Step Solution

1. Step 1: Write the proportion equation
   9,138.88 : 12,610.38 = 5,159.80 : x
2. Step 2: Convert to fraction form
   9,138.88/12,610.38 = 5,159.80/x
3. Step 3: Cross multiply
   9,138.88x = 12,610.38 × 5,159.80
4. Step 4: Simplify right side
   9,138.88x = 65,067,038.72
5. Step 5: Solve for x
   x = 65,067,038.72/9,138.88
6. Step 6: Final answer
   x = 7,119.80