Finding the Fourth Proportional to 20,960.72, 31,442.20 and 5,378.48

Step by Step Solution

1. Step 1: Write the proportion equation
   20,960.72 : 31,442.20 = 5,378.48 : x
2. Step 2: Convert to fraction form
   20,960.72/31,442.20 = 5,378.48/x
3. Step 3: Cross multiply
   20,960.72x = 31,442.20 × 5,378.48
4. Step 4: Simplify right side
   20,960.72x = 169,111,243.86
5. Step 5: Solve for x
   x = 169,111,243.86/20,960.72
6. Step 6: Final answer
   x = 8,068.01