Finding the Fourth Proportional to 3,911.76, 5,399.18 and 2,418.78

Step by Step Solution

1. Step 1: Write the proportion equation
   3,911.76 : 5,399.18 = 2,418.78 : x
2. Step 2: Convert to fraction form
   3,911.76/5,399.18 = 2,418.78/x
3. Step 3: Cross multiply
   3,911.76x = 5,399.18 × 2,418.78
4. Step 4: Simplify right side
   3,911.76x = 13,059,428.60
5. Step 5: Solve for x
   x = 13,059,428.60/3,911.76
6. Step 6: Final answer
   x = 3,338.50