Finding the Fourth Proportional to 21,115.89, 31,690.17 and 10,596.42

Step by Step Solution

1. Step 1: Write the proportion equation
   21,115.89 : 31,690.17 = 10,596.42 : x
2. Step 2: Convert to fraction form
   21,115.89/31,690.17 = 10,596.42/x
3. Step 3: Cross multiply
   21,115.89x = 31,690.17 × 10,596.42
4. Step 4: Simplify right side
   21,115.89x = 335,802,351.19
5. Step 5: Solve for x
   x = 335,802,351.19/21,115.89
6. Step 6: Final answer
   x = 15,902.83