Finding the Fourth Proportional to 13,168.46, 18,181.99 and 8,139.57

Step by Step Solution

1. Step 1: Write the proportion equation
   13,168.46 : 18,181.99 = 8,139.57 : x
2. Step 2: Convert to fraction form
   13,168.46/18,181.99 = 8,139.57/x
3. Step 3: Cross multiply
   13,168.46x = 18,181.99 × 8,139.57
4. Step 4: Simplify right side
   13,168.46x = 147,993,560.00
5. Step 5: Solve for x
   x = 147,993,560.00/13,168.46
6. Step 6: Final answer
   x = 11,238.49