Finding the Fourth Proportional to 2,568.05, 3,543.89 and 1,389.11

Step by Step Solution

1. Step 1: Write the proportion equation
   2,568.05 : 3,543.89 = 1,389.11 : x
2. Step 2: Convert to fraction form
   2,568.05/3,543.89 = 1,389.11/x
3. Step 3: Cross multiply
   2,568.05x = 3,543.89 × 1,389.11
4. Step 4: Simplify right side
   2,568.05x = 4,922,865.37
5. Step 5: Solve for x
   x = 4,922,865.37/2,568.05
6. Step 6: Final answer
   x = 1,916.97