Finding the Fourth Proportional to 11,287.69, 15,606.74 and 9,886.42

Step by Step Solution

1. Step 1: Write the proportion equation
   11,287.69 : 15,606.74 = 9,886.42 : x
2. Step 2: Convert to fraction form
   11,287.69/15,606.74 = 9,886.42/x
3. Step 3: Cross multiply
   11,287.69x = 15,606.74 × 9,886.42
4. Step 4: Simplify right side
   11,287.69x = 154,294,786.47
5. Step 5: Solve for x
   x = 154,294,786.47/11,287.69
6. Step 6: Final answer
   x = 13,669.30