Finding the Fourth Proportional to 20,960.96, 31,442.88 and 7,105.28

Step by Step Solution

1. Step 1: Write the proportion equation
   20,960.96 : 31,442.88 = 7,105.28 : x
2. Step 2: Convert to fraction form
   20,960.96/31,442.88 = 7,105.28/x
3. Step 3: Cross multiply
   20,960.96x = 31,442.88 × 7,105.28
4. Step 4: Simplify right side
   20,960.96x = 223,410,466.41
5. Step 5: Solve for x
   x = 223,410,466.41/20,960.96
6. Step 6: Final answer
   x = 10,658.41