Finding the Fourth Proportional to 1,082.83, 1,623.85 and 389.31

Step by Step Solution

1. Step 1: Write the proportion equation
   1,082.83 : 1,623.85 = 389.31 : x
2. Step 2: Convert to fraction form
   1,082.83/1,623.85 = 389.31/x
3. Step 3: Cross multiply
   1,082.83x = 1,623.85 × 389.31
4. Step 4: Simplify right side
   1,082.83x = 632,179.10
5. Step 5: Solve for x
   x = 632,179.10/1,082.83
6. Step 6: Final answer
   x = 583.82