Finding the Fourth Proportional to 5,148.16, 7,672.72 and 5,105.28

Step by Step Solution

1. Step 1: Write the proportion equation
   5,148.16 : 7,672.72 = 5,105.28 : x
2. Step 2: Convert to fraction form
   5,148.16/7,672.72 = 5,105.28/x
3. Step 3: Cross multiply
   5,148.16x = 7,672.72 × 5,105.28
4. Step 4: Simplify right side
   5,148.16x = 39,171,383.96
5. Step 5: Solve for x
   x = 39,171,383.96/5,148.16
6. Step 6: Final answer
   x = 7,608.81