Finding the Fourth Proportional to 21,123.81, 31,669.11 and 10,588.55

Step by Step Solution

1. Step 1: Write the proportion equation
   21,123.81 : 31,669.11 = 10,588.55 : x
2. Step 2: Convert to fraction form
   21,123.81/31,669.11 = 10,588.55/x
3. Step 3: Cross multiply
   21,123.81x = 31,669.11 × 10,588.55
4. Step 4: Simplify right side
   21,123.81x = 335,329,796.34
5. Step 5: Solve for x
   x = 335,329,796.34/21,123.81
6. Step 6: Final answer
   x = 15,874.49