Finding the Fourth Proportional to 8,979.59, 12,399.67 and 5,628.17

Step by Step Solution

1. Step 1: Write the proportion equation
   8,979.59 : 12,399.67 = 5,628.17 : x
2. Step 2: Convert to fraction form
   8,979.59/12,399.67 = 5,628.17/x
3. Step 3: Cross multiply
   8,979.59x = 12,399.67 × 5,628.17
4. Step 4: Simplify right side
   8,979.59x = 69,787,360.56
5. Step 5: Solve for x
   x = 69,787,360.56/8,979.59
6. Step 6: Final answer
   x = 7,771.78