Finding the Fourth Proportional to 1,038.94, 1,558.71 and 389.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,038.94 : 1,558.71 = 389.72 : x
2. Step 2: Convert to fraction form
   1,038.94/1,558.71 = 389.72/x
3. Step 3: Cross multiply
   1,038.94x = 1,558.71 × 389.72
4. Step 4: Simplify right side
   1,038.94x = 607,458.51
5. Step 5: Solve for x
   x = 607,458.51/1,038.94
6. Step 6: Final answer
   x = 584.69