Finding the Fourth Proportional to 3,913.98, 5,401.34 and 2,145.55

Step by Step Solution

1. Step 1: Write the proportion equation
   3,913.98 : 5,401.34 = 2,145.55 : x
2. Step 2: Convert to fraction form
   3,913.98/5,401.34 = 2,145.55/x
3. Step 3: Cross multiply
   3,913.98x = 5,401.34 × 2,145.55
4. Step 4: Simplify right side
   3,913.98x = 11,588,828.85
5. Step 5: Solve for x
   x = 11,588,828.85/3,913.98
6. Step 6: Final answer
   x = 2,960.88