Finding the Fourth Proportional to 21,131.91, 29,170.53 and 13,867.29

Step by Step Solution

1. Step 1: Write the proportion equation
   21,131.91 : 29,170.53 = 13,867.29 : x
2. Step 2: Convert to fraction form
   21,131.91/29,170.53 = 13,867.29/x
3. Step 3: Cross multiply
   21,131.91x = 29,170.53 × 13,867.29
4. Step 4: Simplify right side
   21,131.91x = 404,516,198.96
5. Step 5: Solve for x
   x = 404,516,198.96/21,131.91
6. Step 6: Final answer
   x = 19,142.43