Finding the Fourth Proportional to 21,111.55, 29,130.37 and 13,156.27

Step by Step Solution

1. Step 1: Write the proportion equation
   21,111.55 : 29,130.37 = 13,156.27 : x
2. Step 2: Convert to fraction form
   21,111.55/29,130.37 = 13,156.27/x
3. Step 3: Cross multiply
   21,111.55x = 29,130.37 × 13,156.27
4. Step 4: Simplify right side
   21,111.55x = 383,247,012.92
5. Step 5: Solve for x
   x = 383,247,012.92/21,111.55
6. Step 6: Final answer
   x = 18,153.43