Finding the Fourth Proportional to 13,100.09, 18,078.57 and 7,131.85

Step by Step Solution

1. Step 1: Write the proportion equation
   13,100.09 : 18,078.57 = 7,131.85 : x
2. Step 2: Convert to fraction form
   13,100.09/18,078.57 = 7,131.85/x
3. Step 3: Cross multiply
   13,100.09x = 18,078.57 × 7,131.85
4. Step 4: Simplify right side
   13,100.09x = 128,933,604.26
5. Step 5: Solve for x
   x = 128,933,604.26/13,100.09
6. Step 6: Final answer
   x = 9,842.20