Finding the Fourth Proportional to 17,278.94, 25,921.15 and 5,431.78

Step by Step Solution

1. Step 1: Write the proportion equation
   17,278.94 : 25,921.15 = 5,431.78 : x
2. Step 2: Convert to fraction form
   17,278.94/25,921.15 = 5,431.78/x
3. Step 3: Cross multiply
   17,278.94x = 25,921.15 × 5,431.78
4. Step 4: Simplify right side
   17,278.94x = 140,797,984.15
5. Step 5: Solve for x
   x = 140,797,984.15/17,278.94
6. Step 6: Final answer
   x = 8,148.53