Finding the Fourth Proportional to 21,749.45, 30,013.91 and 12,189.33

Step by Step Solution

1. Step 1: Write the proportion equation
   21,749.45 : 30,013.91 = 12,189.33 : x
2. Step 2: Convert to fraction form
   21,749.45/30,013.91 = 12,189.33/x
3. Step 3: Cross multiply
   21,749.45x = 30,013.91 × 12,189.33
4. Step 4: Simplify right side
   21,749.45x = 365,849,242.56
5. Step 5: Solve for x
   x = 365,849,242.56/21,749.45
6. Step 6: Final answer
   x = 16,821.08