Finding the Fourth Proportional to 2,564.89, 3,539.55 and 1,385.96

Step by Step Solution

1. Step 1: Write the proportion equation
   2,564.89 : 3,539.55 = 1,385.96 : x
2. Step 2: Convert to fraction form
   2,564.89/3,539.55 = 1,385.96/x
3. Step 3: Cross multiply
   2,564.89x = 3,539.55 × 1,385.96
4. Step 4: Simplify right side
   2,564.89x = 4,905,674.72
5. Step 5: Solve for x
   x = 4,905,674.72/2,564.89
6. Step 6: Final answer
   x = 1,912.63