Finding the Fourth Proportional to 21,121.29, 29,150.04 and 13,859.49

Step by Step Solution

1. Step 1: Write the proportion equation
   21,121.29 : 29,150.04 = 13,859.49 : x
2. Step 2: Convert to fraction form
   21,121.29/29,150.04 = 13,859.49/x
3. Step 3: Cross multiply
   21,121.29x = 29,150.04 × 13,859.49
4. Step 4: Simplify right side
   21,121.29x = 404,004,687.88
5. Step 5: Solve for x
   x = 404,004,687.88/21,121.29
6. Step 6: Final answer
   x = 19,127.84