Finding the Fourth Proportional to 3,891.55, 5,370.27 and 2,123.16

Step by Step Solution

1. Step 1: Write the proportion equation
   3,891.55 : 5,370.27 = 2,123.16 : x
2. Step 2: Convert to fraction form
   3,891.55/5,370.27 = 2,123.16/x
3. Step 3: Cross multiply
   3,891.55x = 5,370.27 × 2,123.16
4. Step 4: Simplify right side
   3,891.55x = 11,401,942.45
5. Step 5: Solve for x
   x = 11,401,942.45/3,891.55
6. Step 6: Final answer
   x = 2,929.92