Finding the Fourth Proportional to 9,579.87, 13,218.78 and 5,387.31

Step by Step Solution

1. Step 1: Write the proportion equation
   9,579.87 : 13,218.78 = 5,387.31 : x
2. Step 2: Convert to fraction form
   9,579.87/13,218.78 = 5,387.31/x
3. Step 3: Cross multiply
   9,579.87x = 13,218.78 × 5,387.31
4. Step 4: Simplify right side
   9,579.87x = 71,213,665.68
5. Step 5: Solve for x
   x = 71,213,665.68/9,579.87
6. Step 6: Final answer
   x = 7,433.68