Finding the Fourth Proportional to 2,815.56, 4,223.61 and 868.05

Step by Step Solution

1. Step 1: Write the proportion equation
   2,815.56 : 4,223.61 = 868.05 : x
2. Step 2: Convert to fraction form
   2,815.56/4,223.61 = 868.05/x
3. Step 3: Cross multiply
   2,815.56x = 4,223.61 × 868.05
4. Step 4: Simplify right side
   2,815.56x = 3,666,304.66
5. Step 5: Solve for x
   x = 3,666,304.66/2,815.56
6. Step 6: Final answer
   x = 1,302.16