Finding the Fourth Proportional to 21,003.34, 28,981.87 and 13,450.37

Step by Step Solution

1. Step 1: Write the proportion equation
   21,003.34 : 28,981.87 = 13,450.37 : x
2. Step 2: Convert to fraction form
   21,003.34/28,981.87 = 13,450.37/x
3. Step 3: Cross multiply
   21,003.34x = 28,981.87 × 13,450.37
4. Step 4: Simplify right side
   21,003.34x = 389,816,911.93
5. Step 5: Solve for x
   x = 389,816,911.93/21,003.34
6. Step 6: Final answer
   x = 18,559.76