Finding the Fourth Proportional to 11,013.57, 15,191.15 and 9,191.53

Step by Step Solution

1. Step 1: Write the proportion equation
   11,013.57 : 15,191.15 = 9,191.53 : x
2. Step 2: Convert to fraction form
   11,013.57/15,191.15 = 9,191.53/x
3. Step 3: Cross multiply
   11,013.57x = 15,191.15 × 9,191.53
4. Step 4: Simplify right side
   11,013.57x = 139,629,798.54
5. Step 5: Solve for x
   x = 139,629,798.54/11,013.57
6. Step 6: Final answer
   x = 12,677.98