Finding the Fourth Proportional to 2,565.15, 3,539.91 and 1,386.23

Step by Step Solution

1. Step 1: Write the proportion equation
   2,565.15 : 3,539.91 = 1,386.23 : x
2. Step 2: Convert to fraction form
   2,565.15/3,539.91 = 1,386.23/x
3. Step 3: Cross multiply
   2,565.15x = 3,539.91 × 1,386.23
4. Step 4: Simplify right side
   2,565.15x = 4,907,116.94
5. Step 5: Solve for x
   x = 4,907,116.94/2,565.15
6. Step 6: Final answer
   x = 1,912.99