Finding the Fourth Proportional to 31,439.18, 43,356.41 and 20,665.02

Step by Step Solution

1. Step 1: Write the proportion equation
   31,439.18 : 43,356.41 = 20,665.02 : x
2. Step 2: Convert to fraction form
   31,439.18/43,356.41 = 20,665.02/x
3. Step 3: Cross multiply
   31,439.18x = 43,356.41 × 20,665.02
4. Step 4: Simplify right side
   31,439.18x = 895,961,079.78
5. Step 5: Solve for x
   x = 895,961,079.78/31,439.18
6. Step 6: Final answer
   x = 28,498.23