Finding the Fourth Proportional to 12,806.40, 17,672.48 and 7,141.31

Step by Step Solution

1. Step 1: Write the proportion equation
   12,806.40 : 17,672.48 = 7,141.31 : x
2. Step 2: Convert to fraction form
   12,806.40/17,672.48 = 7,141.31/x
3. Step 3: Cross multiply
   12,806.40x = 17,672.48 × 7,141.31
4. Step 4: Simplify right side
   12,806.40x = 126,204,726.54
5. Step 5: Solve for x
   x = 126,204,726.54/12,806.40
6. Step 6: Final answer
   x = 9,854.81