Finding the Fourth Proportional to 2,565.48, 3,540.45 and 1,431.20

Step by Step Solution

1. Step 1: Write the proportion equation
   2,565.48 : 3,540.45 = 1,431.20 : x
2. Step 2: Convert to fraction form
   2,565.48/3,540.45 = 1,431.20/x
3. Step 3: Cross multiply
   2,565.48x = 3,540.45 × 1,431.20
4. Step 4: Simplify right side
   2,565.48x = 5,067,074.34
5. Step 5: Solve for x
   x = 5,067,074.34/2,565.48
6. Step 6: Final answer
   x = 1,975.10