Finding the Fourth Proportional to 10,128.09, 13,875.56 and 9,749.38

Step by Step Solution

1. Step 1: Write the proportion equation
   10,128.09 : 13,875.56 = 9,749.38 : x
2. Step 2: Convert to fraction form
   10,128.09/13,875.56 = 9,749.38/x
3. Step 3: Cross multiply
   10,128.09x = 13,875.56 × 9,749.38
4. Step 4: Simplify right side
   10,128.09x = 135,278,107.15
5. Step 5: Solve for x
   x = 135,278,107.15/10,128.09
6. Step 6: Final answer
   x = 13,356.72