Finding the Fourth Proportional to 21,749.79, 30,016.79 and 12,189.63

Step by Step Solution

1. Step 1: Write the proportion equation
   21,749.79 : 30,016.79 = 12,189.63 : x
2. Step 2: Convert to fraction form
   21,749.79/30,016.79 = 12,189.63/x
3. Step 3: Cross multiply
   21,749.79x = 30,016.79 × 12,189.63
4. Step 4: Simplify right side
   21,749.79x = 365,893,519.32
5. Step 5: Solve for x
   x = 365,893,519.32/21,749.79
6. Step 6: Final answer
   x = 16,822.85