Finding the Fourth Proportional to 2,836.20, 4,254.91 and 861.89

Step by Step Solution

1. Step 1: Write the proportion equation
   2,836.20 : 4,254.91 = 861.89 : x
2. Step 2: Convert to fraction form
   2,836.20/4,254.91 = 861.89/x
3. Step 3: Cross multiply
   2,836.20x = 4,254.91 × 861.89
4. Step 4: Simplify right side
   2,836.20x = 3,667,272.86
5. Step 5: Solve for x
   x = 3,667,272.86/2,836.20
6. Step 6: Final answer
   x = 1,293.02