Finding the Fourth Proportional to 9,691.88, 13,372.72 and 5,711.54

Step by Step Solution

1. Step 1: Write the proportion equation
   9,691.88 : 13,372.72 = 5,711.54 : x
2. Step 2: Convert to fraction form
   9,691.88/13,372.72 = 5,711.54/x
3. Step 3: Cross multiply
   9,691.88x = 13,372.72 × 5,711.54
4. Step 4: Simplify right side
   9,691.88x = 76,378,744.05
5. Step 5: Solve for x
   x = 76,378,744.05/9,691.88
6. Step 6: Final answer
   x = 7,880.70