Finding the Fourth Proportional to 2,280.55, 3,418.80 and 819.31

Step by Step Solution

1. Step 1: Write the proportion equation
   2,280.55 : 3,418.80 = 819.31 : x
2. Step 2: Convert to fraction form
   2,280.55/3,418.80 = 819.31/x
3. Step 3: Cross multiply
   2,280.55x = 3,418.80 × 819.31
4. Step 4: Simplify right side
   2,280.55x = 2,801,057.03
5. Step 5: Solve for x
   x = 2,801,057.03/2,280.55
6. Step 6: Final answer
   x = 1,228.24