Finding the Fourth Proportional to 2,569.42, 3,545.79 and 1,390.49

Step by Step Solution

1. Step 1: Write the proportion equation
   2,569.42 : 3,545.79 = 1,390.49 : x
2. Step 2: Convert to fraction form
   2,569.42/3,545.79 = 1,390.49/x
3. Step 3: Cross multiply
   2,569.42x = 3,545.79 × 1,390.49
4. Step 4: Simplify right side
   2,569.42x = 4,930,380.89
5. Step 5: Solve for x
   x = 4,930,380.89/2,569.42
6. Step 6: Final answer
   x = 1,918.87