Finding the Fourth Proportional to 11,103.57, 15,324.66 and 7,128.90

Step by Step Solution

1. Step 1: Write the proportion equation
   11,103.57 : 15,324.66 = 7,128.90 : x
2. Step 2: Convert to fraction form
   11,103.57/15,324.66 = 7,128.90/x
3. Step 3: Cross multiply
   11,103.57x = 15,324.66 × 7,128.90
4. Step 4: Simplify right side
   11,103.57x = 109,247,968.67
5. Step 5: Solve for x
   x = 109,247,968.67/11,103.57
6. Step 6: Final answer
   x = 9,838.99