Finding the Fourth Proportional to 8,688.72, 13,035.78 and 5,911.32

Step by Step Solution

1. Step 1: Write the proportion equation
   8,688.72 : 13,035.78 = 5,911.32 : x
2. Step 2: Convert to fraction form
   8,688.72/13,035.78 = 5,911.32/x
3. Step 3: Cross multiply
   8,688.72x = 13,035.78 × 5,911.32
4. Step 4: Simplify right side
   8,688.72x = 77,058,667.03
5. Step 5: Solve for x
   x = 77,058,667.03/8,688.72
6. Step 6: Final answer
   x = 8,868.82