Finding the Fourth Proportional to 2,205.33, 3,309.47 and 818.72

Step by Step Solution

1. Step 1: Write the proportion equation
   2,205.33 : 3,309.47 = 818.72 : x
2. Step 2: Convert to fraction form
   2,205.33/3,309.47 = 818.72/x
3. Step 3: Cross multiply
   2,205.33x = 3,309.47 × 818.72
4. Step 4: Simplify right side
   2,205.33x = 2,709,529.28
5. Step 5: Solve for x
   x = 2,709,529.28/2,205.33
6. Step 6: Final answer
   x = 1,228.63