Finding the Fourth Proportional to 21,558.88, 29,759.12 and 13,606.28

Step by Step Solution

1. Step 1: Write the proportion equation
   21,558.88 : 29,759.12 = 13,606.28 : x
2. Step 2: Convert to fraction form
   21,558.88/29,759.12 = 13,606.28/x
3. Step 3: Cross multiply
   21,558.88x = 29,759.12 × 13,606.28
4. Step 4: Simplify right side
   21,558.88x = 404,910,919.27
5. Step 5: Solve for x
   x = 404,910,919.27/21,558.88
6. Step 6: Final answer
   x = 18,781.63