Finding the Fourth Proportional to 9,901.84, 13,665.36 and 8,128.48

Step by Step Solution

1. Step 1: Write the proportion equation
   9,901.84 : 13,665.36 = 8,128.48 : x
2. Step 2: Convert to fraction form
   9,901.84/13,665.36 = 8,128.48/x
3. Step 3: Cross multiply
   9,901.84x = 13,665.36 × 8,128.48
4. Step 4: Simplify right side
   9,901.84x = 111,078,605.45
5. Step 5: Solve for x
   x = 111,078,605.45/9,901.84
6. Step 6: Final answer
   x = 11,217.98