Finding the Fourth Proportional to 2,559.38, 3,531.90 and 1,440.30

Step by Step Solution

1. Step 1: Write the proportion equation
   2,559.38 : 3,531.90 = 1,440.30 : x
2. Step 2: Convert to fraction form
   2,559.38/3,531.90 = 1,440.30/x
3. Step 3: Cross multiply
   2,559.38x = 3,531.90 × 1,440.30
4. Step 4: Simplify right side
   2,559.38x = 5,086,995.57
5. Step 5: Solve for x
   x = 5,086,995.57/2,559.38
6. Step 6: Final answer
   x = 1,987.59