Finding the Fourth Proportional to 21,057.98, 29,064.89 and 13,889.17

Step by Step Solution

1. Step 1: Write the proportion equation
   21,057.98 : 29,064.89 = 13,889.17 : x
2. Step 2: Convert to fraction form
   21,057.98/29,064.89 = 13,889.17/x
3. Step 3: Cross multiply
   21,057.98x = 29,064.89 × 13,889.17
4. Step 4: Simplify right side
   21,057.98x = 403,687,269.30
5. Step 5: Solve for x
   x = 403,687,269.30/21,057.98
6. Step 6: Final answer
   x = 19,170.28