Finding the Fourth Proportional to 2,706.39, 4,059.72 and 857.55

Step by Step Solution

1. Step 1: Write the proportion equation
   2,706.39 : 4,059.72 = 857.55 : x
2. Step 2: Convert to fraction form
   2,706.39/4,059.72 = 857.55/x
3. Step 3: Cross multiply
   2,706.39x = 4,059.72 × 857.55
4. Step 4: Simplify right side
   2,706.39x = 3,481,412.89
5. Step 5: Solve for x
   x = 3,481,412.89/2,706.39
6. Step 6: Final answer
   x = 1,286.37