Finding the Fourth Proportional to 3,478.78, 5,218.38 and 1,139.03

Step by Step Solution

1. Step 1: Write the proportion equation
   3,478.78 : 5,218.38 = 1,139.03 : x
2. Step 2: Convert to fraction form
   3,478.78/5,218.38 = 1,139.03/x
3. Step 3: Cross multiply
   3,478.78x = 5,218.38 × 1,139.03
4. Step 4: Simplify right side
   3,478.78x = 5,943,891.37
5. Step 5: Solve for x
   x = 5,943,891.37/3,478.78
6. Step 6: Final answer
   x = 1,708.61