Finding the Fourth Proportional to 9,578.89, 13,218.99 and 5,387.14

Step by Step Solution

1. Step 1: Write the proportion equation
   9,578.89 : 13,218.99 = 5,387.14 : x
2. Step 2: Convert to fraction form
   9,578.89/13,218.99 = 5,387.14/x
3. Step 3: Cross multiply
   9,578.89x = 13,218.99 × 5,387.14
4. Step 4: Simplify right side
   9,578.89x = 71,212,483.69
5. Step 5: Solve for x
   x = 71,212,483.69/9,578.89
6. Step 6: Final answer
   x = 7,434.32