Finding the Fourth Proportional to 8,871.72, 12,238.20 and 5,513.40

Step by Step Solution

1. Step 1: Write the proportion equation
   8,871.72 : 12,238.20 = 5,513.40 : x
2. Step 2: Convert to fraction form
   8,871.72/12,238.20 = 5,513.40/x
3. Step 3: Cross multiply
   8,871.72x = 12,238.20 × 5,513.40
4. Step 4: Simplify right side
   8,871.72x = 67,474,091.88
5. Step 5: Solve for x
   x = 67,474,091.88/8,871.72
6. Step 6: Final answer
   x = 7,605.53