Finding the Fourth Proportional to 1,103.78, 1,653.37 and 519.28

Step by Step Solution

1. Step 1: Write the proportion equation
   1,103.78 : 1,653.37 = 519.28 : x
2. Step 2: Convert to fraction form
   1,103.78/1,653.37 = 519.28/x
3. Step 3: Cross multiply
   1,103.78x = 1,653.37 × 519.28
4. Step 4: Simplify right side
   1,103.78x = 858,556.54
5. Step 5: Solve for x
   x = 858,556.54/1,103.78
6. Step 6: Final answer
   x = 777.83