Finding the Fourth Proportional to 21,112.89, 31,665.02 and 12,341.13

Step by Step Solution

1. Step 1: Write the proportion equation
   21,112.89 : 31,665.02 = 12,341.13 : x
2. Step 2: Convert to fraction form
   21,112.89/31,665.02 = 12,341.13/x
3. Step 3: Cross multiply
   21,112.89x = 31,665.02 × 12,341.13
4. Step 4: Simplify right side
   21,112.89x = 390,782,066.57
5. Step 5: Solve for x
   x = 390,782,066.57/21,112.89
6. Step 6: Final answer
   x = 18,509.17