Finding the Fourth Proportional to 5,791.72, 7,992.56 and 3,139.12

Step by Step Solution

1. Step 1: Write the proportion equation
   5,791.72 : 7,992.56 = 3,139.12 : x
2. Step 2: Convert to fraction form
   5,791.72/7,992.56 = 3,139.12/x
3. Step 3: Cross multiply
   5,791.72x = 7,992.56 × 3,139.12
4. Step 4: Simplify right side
   5,791.72x = 25,089,604.95
5. Step 5: Solve for x
   x = 25,089,604.95/5,791.72
6. Step 6: Final answer
   x = 4,331.98