Finding the Fourth Proportional to 2,589.05, 3,572.78 and 1,439.06

Step by Step Solution

1. Step 1: Write the proportion equation
   2,589.05 : 3,572.78 = 1,439.06 : x
2. Step 2: Convert to fraction form
   2,589.05/3,572.78 = 1,439.06/x
3. Step 3: Cross multiply
   2,589.05x = 3,572.78 × 1,439.06
4. Step 4: Simplify right side
   2,589.05x = 5,141,419.73
5. Step 5: Solve for x
   x = 5,141,419.73/2,589.05
6. Step 6: Final answer
   x = 1,985.83