Finding the Fourth Proportional to 1,039.82, 1,558.91 and 519.55

Step by Step Solution

1. Step 1: Write the proportion equation
   1,039.82 : 1,558.91 = 519.55 : x
2. Step 2: Convert to fraction form
   1,039.82/1,558.91 = 519.55/x
3. Step 3: Cross multiply
   1,039.82x = 1,558.91 × 519.55
4. Step 4: Simplify right side
   1,039.82x = 809,931.69
5. Step 5: Solve for x
   x = 809,931.69/1,039.82
6. Step 6: Final answer
   x = 778.92