Finding the Fourth Proportional to 21,105.36, 31,662.72 and 7,957.85

Step by Step Solution

1. Step 1: Write the proportion equation
   21,105.36 : 31,662.72 = 7,957.85 : x
2. Step 2: Convert to fraction form
   21,105.36/31,662.72 = 7,957.85/x
3. Step 3: Cross multiply
   21,105.36x = 31,662.72 × 7,957.85
4. Step 4: Simplify right side
   21,105.36x = 251,967,176.35
5. Step 5: Solve for x
   x = 251,967,176.35/21,105.36
6. Step 6: Final answer
   x = 11,938.54