Finding the Fourth Proportional to 2,570.15, 3,546.81 and 1,391.21

Step by Step Solution

1. Step 1: Write the proportion equation
   2,570.15 : 3,546.81 = 1,391.21 : x
2. Step 2: Convert to fraction form
   2,570.15/3,546.81 = 1,391.21/x
3. Step 3: Cross multiply
   2,570.15x = 3,546.81 × 1,391.21
4. Step 4: Simplify right side
   2,570.15x = 4,934,357.54
5. Step 5: Solve for x
   x = 4,934,357.54/2,570.15
6. Step 6: Final answer
   x = 1,919.87