Finding the Fourth Proportional to 1,042.52, 1,562.84 and 392.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,042.52 : 1,562.84 = 392.78 : x
2. Step 2: Convert to fraction form
   1,042.52/1,562.84 = 392.78/x
3. Step 3: Cross multiply
   1,042.52x = 1,562.84 × 392.78
4. Step 4: Simplify right side
   1,042.52x = 613,852.30
5. Step 5: Solve for x
   x = 613,852.30/1,042.52
6. Step 6: Final answer
   x = 588.82