Finding the Fourth Proportional to 5,423.72, 8,128.71 and 2,787.48

Step by Step Solution

1. Step 1: Write the proportion equation
   5,423.72 : 8,128.71 = 2,787.48 : x
2. Step 2: Convert to fraction form
   5,423.72/8,128.71 = 2,787.48/x
3. Step 3: Cross multiply
   5,423.72x = 8,128.71 × 2,787.48
4. Step 4: Simplify right side
   5,423.72x = 22,658,616.55
5. Step 5: Solve for x
   x = 22,658,616.55/5,423.72
6. Step 6: Final answer
   x = 4,177.69