Finding the Fourth Proportional to 2,564.20, 3,538.60 and 1,385.27

Step by Step Solution

1. Step 1: Write the proportion equation
   2,564.20 : 3,538.60 = 1,385.27 : x
2. Step 2: Convert to fraction form
   2,564.20/3,538.60 = 1,385.27/x
3. Step 3: Cross multiply
   2,564.20x = 3,538.60 × 1,385.27
4. Step 4: Simplify right side
   2,564.20x = 4,901,916.42
5. Step 5: Solve for x
   x = 4,901,916.42/2,564.20
6. Step 6: Final answer
   x = 1,911.67