Finding the Fourth Proportional to 1,004.31, 1,385.91 and 584.64

Step by Step Solution

1. Step 1: Write the proportion equation
   1,004.31 : 1,385.91 = 584.64 : x
2. Step 2: Convert to fraction form
   1,004.31/1,385.91 = 584.64/x
3. Step 3: Cross multiply
   1,004.31x = 1,385.91 × 584.64
4. Step 4: Simplify right side
   1,004.31x = 810,258.42
5. Step 5: Solve for x
   x = 810,258.42/1,004.31
6. Step 6: Final answer
   x = 806.78