Finding the Fourth Proportional to 13,443.56, 18,552.90 and 8,139.72

Step by Step Solution

1. Step 1: Write the proportion equation
   13,443.56 : 18,552.90 = 8,139.72 : x
2. Step 2: Convert to fraction form
   13,443.56/18,552.90 = 8,139.72/x
3. Step 3: Cross multiply
   13,443.56x = 18,552.90 × 8,139.72
4. Step 4: Simplify right side
   13,443.56x = 151,015,411.19
5. Step 5: Solve for x
   x = 151,015,411.19/13,443.56
6. Step 6: Final answer
   x = 11,233.29