Finding the Fourth Proportional to 11,687.16, 17,522.10 and 4,287.72

Step by Step Solution

1. Step 1: Write the proportion equation
   11,687.16 : 17,522.10 = 4,287.72 : x
2. Step 2: Convert to fraction form
   11,687.16/17,522.10 = 4,287.72/x
3. Step 3: Cross multiply
   11,687.16x = 17,522.10 × 4,287.72
4. Step 4: Simplify right side
   11,687.16x = 75,129,858.61
5. Step 5: Solve for x
   x = 75,129,858.61/11,687.16
6. Step 6: Final answer
   x = 6,428.41