Finding the Fourth Proportional to 10,115.91, 15,141.42 and 5,424.12

Step by Step Solution

1. Step 1: Write the proportion equation
   10,115.91 : 15,141.42 = 5,424.12 : x
2. Step 2: Convert to fraction form
   10,115.91/15,141.42 = 5,424.12/x
3. Step 3: Cross multiply
   10,115.91x = 15,141.42 × 5,424.12
4. Step 4: Simplify right side
   10,115.91x = 82,128,879.05
5. Step 5: Solve for x
   x = 82,128,879.05/10,115.91
6. Step 6: Final answer
   x = 8,118.78