Finding the Fourth Proportional to 21,150.72, 29,187.92 and 11,719.28

Step by Step Solution

1. Step 1: Write the proportion equation
   21,150.72 : 29,187.92 = 11,719.28 : x
2. Step 2: Convert to fraction form
   21,150.72/29,187.92 = 11,719.28/x
3. Step 3: Cross multiply
   21,150.72x = 29,187.92 × 11,719.28
4. Step 4: Simplify right side
   21,150.72x = 342,061,407.10
5. Step 5: Solve for x
   x = 342,061,407.10/21,150.72
6. Step 6: Final answer
   x = 16,172.57