Finding the Fourth Proportional to 11,691.14, 16,128.15 and 8,499.48

Step by Step Solution

1. Step 1: Write the proportion equation
   11,691.14 : 16,128.15 = 8,499.48 : x
2. Step 2: Convert to fraction form
   11,691.14/16,128.15 = 8,499.48/x
3. Step 3: Cross multiply
   11,691.14x = 16,128.15 × 8,499.48
4. Step 4: Simplify right side
   11,691.14x = 137,080,886.73
5. Step 5: Solve for x
   x = 137,080,886.73/11,691.14
6. Step 6: Final answer
   x = 11,725.20