Finding the Fourth Proportional to 21,123.54, 29,124 and 13,556.52

Step by Step Solution

1. Step 1: Write the proportion equation
   21,123.54 : 29,124 = 13,556.52 : x
2. Step 2: Convert to fraction form
   21,123.54/29,124 = 13,556.52/x
3. Step 3: Cross multiply
   21,123.54x = 29,124 × 13,556.52
4. Step 4: Simplify right side
   21,123.54x = 394,820,088.48
5. Step 5: Solve for x
   x = 394,820,088.48/21,123.54
6. Step 6: Final answer
   x = 18,691.00