Finding the Fourth Proportional to 2,570.69, 3,855.60 and 839.31

Step by Step Solution

1. Step 1: Write the proportion equation
   2,570.69 : 3,855.60 = 839.31 : x
2. Step 2: Convert to fraction form
   2,570.69/3,855.60 = 839.31/x
3. Step 3: Cross multiply
   2,570.69x = 3,855.60 × 839.31
4. Step 4: Simplify right side
   2,570.69x = 3,236,050.87
5. Step 5: Solve for x
   x = 3,236,050.87/2,570.69
6. Step 6: Final answer
   x = 1,258.83