Finding the Fourth Proportional to 9,826.31, 13,561.72 and 5,578.43

Step by Step Solution

1. Step 1: Write the proportion equation
   9,826.31 : 13,561.72 = 5,578.43 : x
2. Step 2: Convert to fraction form
   9,826.31/13,561.72 = 5,578.43/x
3. Step 3: Cross multiply
   9,826.31x = 13,561.72 × 5,578.43
4. Step 4: Simplify right side
   9,826.31x = 75,653,023.94
5. Step 5: Solve for x
   x = 75,653,023.94/9,826.31
6. Step 6: Final answer
   x = 7,699.02