Finding the Fourth Proportional to 9,885.05, 13,641.56 and 5,408.78

Step by Step Solution

1. Step 1: Write the proportion equation
   9,885.05 : 13,641.56 = 5,408.78 : x
2. Step 2: Convert to fraction form
   9,885.05/13,641.56 = 5,408.78/x
3. Step 3: Cross multiply
   9,885.05x = 13,641.56 × 5,408.78
4. Step 4: Simplify right side
   9,885.05x = 73,784,101.65
5. Step 5: Solve for x
   x = 73,784,101.65/9,885.05
6. Step 6: Final answer
   x = 7,464.22