Finding the Fourth Proportional to 13,105.20, 18,085.48 and 7,137.18

Step by Step Solution

1. Step 1: Write the proportion equation
   13,105.20 : 18,085.48 = 7,137.18 : x
2. Step 2: Convert to fraction form
   13,105.20/18,085.48 = 7,137.18/x
3. Step 3: Cross multiply
   13,105.20x = 18,085.48 × 7,137.18
4. Step 4: Simplify right side
   13,105.20x = 129,079,326.15
5. Step 5: Solve for x
   x = 129,079,326.15/13,105.20
6. Step 6: Final answer
   x = 9,849.47