Finding the Fourth Proportional to 21,112.14, 31,663.89 and 12,340.38

Step by Step Solution

1. Step 1: Write the proportion equation
   21,112.14 : 31,663.89 = 12,340.38 : x
2. Step 2: Convert to fraction form
   21,112.14/31,663.89 = 12,340.38/x
3. Step 3: Cross multiply
   21,112.14x = 31,663.89 × 12,340.38
4. Step 4: Simplify right side
   21,112.14x = 390,744,434.88
5. Step 5: Solve for x
   x = 390,744,434.88/21,112.14
6. Step 6: Final answer
   x = 18,508.04