Finding the Fourth Proportional to 9,321.78, 12,865.91 and 5,288.69

Step by Step Solution

1. Step 1: Write the proportion equation
   9,321.78 : 12,865.91 = 5,288.69 : x
2. Step 2: Convert to fraction form
   9,321.78/12,865.91 = 5,288.69/x
3. Step 3: Cross multiply
   9,321.78x = 12,865.91 × 5,288.69
4. Step 4: Simplify right side
   9,321.78x = 68,043,742.91
5. Step 5: Solve for x
   x = 68,043,742.91/9,321.78
6. Step 6: Final answer
   x = 7,299.44