Finding the Fourth Proportional to 2,872.56, 4,309.50 and 820.56

Step by Step Solution

1. Step 1: Write the proportion equation
   2,872.56 : 4,309.50 = 820.56 : x
2. Step 2: Convert to fraction form
   2,872.56/4,309.50 = 820.56/x
3. Step 3: Cross multiply
   2,872.56x = 4,309.50 × 820.56
4. Step 4: Simplify right side
   2,872.56x = 3,536,203.32
5. Step 5: Solve for x
   x = 3,536,203.32/2,872.56
6. Step 6: Final answer
   x = 1,231.03