Finding the Fourth Proportional to 1,040.33, 1,561.41 and 578.63

Step by Step Solution

1. Step 1: Write the proportion equation
   1,040.33 : 1,561.41 = 578.63 : x
2. Step 2: Convert to fraction form
   1,040.33/1,561.41 = 578.63/x
3. Step 3: Cross multiply
   1,040.33x = 1,561.41 × 578.63
4. Step 4: Simplify right side
   1,040.33x = 903,470.86
5. Step 5: Solve for x
   x = 903,470.86/1,040.33
6. Step 6: Final answer
   x = 868.45