Finding the Fourth Proportional to 1,119.57, 1,678.83 and 389.05

Step by Step Solution

1. Step 1: Write the proportion equation
   1,119.57 : 1,678.83 = 389.05 : x
2. Step 2: Convert to fraction form
   1,119.57/1,678.83 = 389.05/x
3. Step 3: Cross multiply
   1,119.57x = 1,678.83 × 389.05
4. Step 4: Simplify right side
   1,119.57x = 653,152.60
5. Step 5: Solve for x
   x = 653,152.60/1,119.57
6. Step 6: Final answer
   x = 583.39