Finding the Fourth Proportional to 21,661.75, 32,418.69 and 18,155.72

Step by Step Solution

1. Step 1: Write the proportion equation
   21,661.75 : 32,418.69 = 18,155.72 : x
2. Step 2: Convert to fraction form
   21,661.75/32,418.69 = 18,155.72/x
3. Step 3: Cross multiply
   21,661.75x = 32,418.69 × 18,155.72
4. Step 4: Simplify right side
   21,661.75x = 588,584,496.31
5. Step 5: Solve for x
   x = 588,584,496.31/21,661.75
6. Step 6: Final answer
   x = 27,171.61