Finding the Fourth Proportional to 2,399.50, 3,599.61 and 860.86

Step by Step Solution

1. Step 1: Write the proportion equation
   2,399.50 : 3,599.61 = 860.86 : x
2. Step 2: Convert to fraction form
   2,399.50/3,599.61 = 860.86/x
3. Step 3: Cross multiply
   2,399.50x = 3,599.61 × 860.86
4. Step 4: Simplify right side
   2,399.50x = 3,098,760.26
5. Step 5: Solve for x
   x = 3,098,760.26/2,399.50
6. Step 6: Final answer
   x = 1,291.42