Finding the Fourth Proportional to 23,128.20, 31,916.90 and 13,056.73

Step by Step Solution

1. Step 1: Write the proportion equation
   23,128.20 : 31,916.90 = 13,056.73 : x
2. Step 2: Convert to fraction form
   23,128.20/31,916.90 = 13,056.73/x
3. Step 3: Cross multiply
   23,128.20x = 31,916.90 × 13,056.73
4. Step 4: Simplify right side
   23,128.20x = 416,730,298.59
5. Step 5: Solve for x
   x = 416,730,298.59/23,128.20
6. Step 6: Final answer
   x = 18,018.28