Finding the Fourth Proportional to 2,219.30, 3,328.58 and 813.43

Step by Step Solution

1. Step 1: Write the proportion equation
   2,219.30 : 3,328.58 = 813.43 : x
2. Step 2: Convert to fraction form
   2,219.30/3,328.58 = 813.43/x
3. Step 3: Cross multiply
   2,219.30x = 3,328.58 × 813.43
4. Step 4: Simplify right side
   2,219.30x = 2,707,549.72
5. Step 5: Solve for x
   x = 2,707,549.72/2,219.30
6. Step 6: Final answer
   x = 1,220.00