Finding the Fourth Proportional to 2,639.42, 3,958.14 and 1,078.59

Step by Step Solution

1. Step 1: Write the proportion equation
   2,639.42 : 3,958.14 = 1,078.59 : x
2. Step 2: Convert to fraction form
   2,639.42/3,958.14 = 1,078.59/x
3. Step 3: Cross multiply
   2,639.42x = 3,958.14 × 1,078.59
4. Step 4: Simplify right side
   2,639.42x = 4,269,210.22
5. Step 5: Solve for x
   x = 4,269,210.22/2,639.42
6. Step 6: Final answer
   x = 1,617.48