Finding the Fourth Proportional to 5,138.63, 7,711.69 and 3,971.55

Step by Step Solution

1. Step 1: Write the proportion equation
   5,138.63 : 7,711.69 = 3,971.55 : x
2. Step 2: Convert to fraction form
   5,138.63/7,711.69 = 3,971.55/x
3. Step 3: Cross multiply
   5,138.63x = 7,711.69 × 3,971.55
4. Step 4: Simplify right side
   5,138.63x = 30,627,362.42
5. Step 5: Solve for x
   x = 30,627,362.42/5,138.63
6. Step 6: Final answer
   x = 5,960.22