Finding the Fourth Proportional to 8,871.39, 13,311.59 and 5,911.86

Step by Step Solution

1. Step 1: Write the proportion equation
   8,871.39 : 13,311.59 = 5,911.86 : x
2. Step 2: Convert to fraction form
   8,871.39/13,311.59 = 5,911.86/x
3. Step 3: Cross multiply
   8,871.39x = 13,311.59 × 5,911.86
4. Step 4: Simplify right side
   8,871.39x = 78,696,256.46
5. Step 5: Solve for x
   x = 78,696,256.46/8,871.39
6. Step 6: Final answer
   x = 8,870.79