Finding the Fourth Proportional to 9,258.39, 12,776.25 and 5,280.78

Step by Step Solution

1. Step 1: Write the proportion equation
   9,258.39 : 12,776.25 = 5,280.78 : x
2. Step 2: Convert to fraction form
   9,258.39/12,776.25 = 5,280.78/x
3. Step 3: Cross multiply
   9,258.39x = 12,776.25 × 5,280.78
4. Step 4: Simplify right side
   9,258.39x = 67,468,578.68
5. Step 5: Solve for x
   x = 67,468,578.68/9,258.39
6. Step 6: Final answer
   x = 7,287.29