Finding the Fourth Proportional to 2,589.95, 3,885.15 and 810.89

Step by Step Solution

1. Step 1: Write the proportion equation
   2,589.95 : 3,885.15 = 810.89 : x
2. Step 2: Convert to fraction form
   2,589.95/3,885.15 = 810.89/x
3. Step 3: Cross multiply
   2,589.95x = 3,885.15 × 810.89
4. Step 4: Simplify right side
   2,589.95x = 3,150,429.28
5. Step 5: Solve for x
   x = 3,150,429.28/2,589.95
6. Step 6: Final answer
   x = 1,216.41