Finding the Fourth Proportional to 10,689.28, 16,106.89 and 8,784.16

Step by Step Solution

1. Step 1: Write the proportion equation
   10,689.28 : 16,106.89 = 8,784.16 : x
2. Step 2: Convert to fraction form
   10,689.28/16,106.89 = 8,784.16/x
3. Step 3: Cross multiply
   10,689.28x = 16,106.89 × 8,784.16
4. Step 4: Simplify right side
   10,689.28x = 141,485,498.86
5. Step 5: Solve for x
   x = 141,485,498.86/10,689.28
6. Step 6: Final answer
   x = 13,236.20