Finding the Fourth Proportional to 15,689.27, 21,651.23 and 8,616.15

Step by Step Solution

1. Step 1: Write the proportion equation
   15,689.27 : 21,651.23 = 8,616.15 : x
2. Step 2: Convert to fraction form
   15,689.27/21,651.23 = 8,616.15/x
3. Step 3: Cross multiply
   15,689.27x = 21,651.23 × 8,616.15
4. Step 4: Simplify right side
   15,689.27x = 186,550,266.90
5. Step 5: Solve for x
   x = 186,550,266.90/15,689.27
6. Step 6: Final answer
   x = 11,890.31