Finding the Fourth Proportional to 2,439.75, 3,659.69 and 879.89

Step by Step Solution

1. Step 1: Write the proportion equation
   2,439.75 : 3,659.69 = 879.89 : x
2. Step 2: Convert to fraction form
   2,439.75/3,659.69 = 879.89/x
3. Step 3: Cross multiply
   2,439.75x = 3,659.69 × 879.89
4. Step 4: Simplify right side
   2,439.75x = 3,220,101.94
5. Step 5: Solve for x
   x = 3,220,101.94/2,439.75
6. Step 6: Final answer
   x = 1,319.85