Finding the Fourth Proportional to 1,042.38, 1,438.49 and 570.28

Step by Step Solution

1. Step 1: Write the proportion equation
   1,042.38 : 1,438.49 = 570.28 : x
2. Step 2: Convert to fraction form
   1,042.38/1,438.49 = 570.28/x
3. Step 3: Cross multiply
   1,042.38x = 1,438.49 × 570.28
4. Step 4: Simplify right side
   1,042.38x = 820,339.23
5. Step 5: Solve for x
   x = 820,339.23/1,042.38
6. Step 6: Final answer
   x = 786.99