Finding the Fourth Proportional to 2,561.05, 3,535.49 and 1,618.21

Step by Step Solution

1. Step 1: Write the proportion equation
   2,561.05 : 3,535.49 = 1,618.21 : x
2. Step 2: Convert to fraction form
   2,561.05/3,535.49 = 1,618.21/x
3. Step 3: Cross multiply
   2,561.05x = 3,535.49 × 1,618.21
4. Step 4: Simplify right side
   2,561.05x = 5,721,165.27
5. Step 5: Solve for x
   x = 5,721,165.27/2,561.05
6. Step 6: Final answer
   x = 2,233.91