Finding the Fourth Proportional to 2,557.89, 3,529.80 and 1,564.20

Step by Step Solution

1. Step 1: Write the proportion equation
   2,557.89 : 3,529.80 = 1,564.20 : x
2. Step 2: Convert to fraction form
   2,557.89/3,529.80 = 1,564.20/x
3. Step 3: Cross multiply
   2,557.89x = 3,529.80 × 1,564.20
4. Step 4: Simplify right side
   2,557.89x = 5,521,313.16
5. Step 5: Solve for x
   x = 5,521,313.16/2,557.89
6. Step 6: Final answer
   x = 2,158.54