Finding the Fourth Proportional to 9,728.80, 13,435.92 and 7,648.16

Step by Step Solution

1. Step 1: Write the proportion equation
   9,728.80 : 13,435.92 = 7,648.16 : x
2. Step 2: Convert to fraction form
   9,728.80/13,435.92 = 7,648.16/x
3. Step 3: Cross multiply
   9,728.80x = 13,435.92 × 7,648.16
4. Step 4: Simplify right side
   9,728.80x = 102,760,065.91
5. Step 5: Solve for x
   x = 102,760,065.91/9,728.80
6. Step 6: Final answer
   x = 10,562.46