Finding the Fourth Proportional to 2,570.27, 3,855.37 and 815.27

Step by Step Solution

1. Step 1: Write the proportion equation
   2,570.27 : 3,855.37 = 815.27 : x
2. Step 2: Convert to fraction form
   2,570.27/3,855.37 = 815.27/x
3. Step 3: Cross multiply
   2,570.27x = 3,855.37 × 815.27
4. Step 4: Simplify right side
   2,570.27x = 3,143,167.50
5. Step 5: Solve for x
   x = 3,143,167.50/2,570.27
6. Step 6: Final answer
   x = 1,222.89