Finding the Fourth Proportional to 22,555.15, 31,128.78 and 13,123.69

Step by Step Solution

1. Step 1: Write the proportion equation
   22,555.15 : 31,128.78 = 13,123.69 : x
2. Step 2: Convert to fraction form
   22,555.15/31,128.78 = 13,123.69/x
3. Step 3: Cross multiply
   22,555.15x = 31,128.78 × 13,123.69
4. Step 4: Simplify right side
   22,555.15x = 408,524,458.80
5. Step 5: Solve for x
   x = 408,524,458.80/22,555.15
6. Step 6: Final answer
   x = 18,112.25