Finding the Fourth Proportional to 21,666.42, 29,912.55 and 13,715.46

Step by Step Solution

1. Step 1: Write the proportion equation
   21,666.42 : 29,912.55 = 13,715.46 : x
2. Step 2: Convert to fraction form
   21,666.42/29,912.55 = 13,715.46/x
3. Step 3: Cross multiply
   21,666.42x = 29,912.55 × 13,715.46
4. Step 4: Simplify right side
   21,666.42x = 410,264,383.02
5. Step 5: Solve for x
   x = 410,264,383.02/21,666.42
6. Step 6: Final answer
   x = 18,935.49