Finding the Fourth Proportional to 9,706.72, 13,395.10 and 5,728.20

Step by Step Solution

1. Step 1: Write the proportion equation
   9,706.72 : 13,395.10 = 5,728.20 : x
2. Step 2: Convert to fraction form
   9,706.72/13,395.10 = 5,728.20/x
3. Step 3: Cross multiply
   9,706.72x = 13,395.10 × 5,728.20
4. Step 4: Simplify right side
   9,706.72x = 76,729,811.82
5. Step 5: Solve for x
   x = 76,729,811.82/9,706.72
6. Step 6: Final answer
   x = 7,904.81