Finding the Fourth Proportional to 9,288.87, 12,819.51 and 5,309.21

Step by Step Solution

1. Step 1: Write the proportion equation
   9,288.87 : 12,819.51 = 5,309.21 : x
2. Step 2: Convert to fraction form
   9,288.87/12,819.51 = 5,309.21/x
3. Step 3: Cross multiply
   9,288.87x = 12,819.51 × 5,309.21
4. Step 4: Simplify right side
   9,288.87x = 68,061,470.69
5. Step 5: Solve for x
   x = 68,061,470.69/9,288.87
6. Step 6: Final answer
   x = 7,327.21