Finding the Fourth Proportional to 9,658.50, 13,328.79 and 5,679.78

Step by Step Solution

1. Step 1: Write the proportion equation
   9,658.50 : 13,328.79 = 5,679.78 : x
2. Step 2: Convert to fraction form
   9,658.50/13,328.79 = 5,679.78/x
3. Step 3: Cross multiply
   9,658.50x = 13,328.79 × 5,679.78
4. Step 4: Simplify right side
   9,658.50x = 75,704,594.87
5. Step 5: Solve for x
   x = 75,704,594.87/9,658.50
6. Step 6: Final answer
   x = 7,838.13