Finding the Fourth Proportional to 2,640.89, 3,636.45 and 2,505.35

Step by Step Solution

1. Step 1: Write the proportion equation
   2,640.89 : 3,636.45 = 2,505.35 : x
2. Step 2: Convert to fraction form
   2,640.89/3,636.45 = 2,505.35/x
3. Step 3: Cross multiply
   2,640.89x = 3,636.45 × 2,505.35
4. Step 4: Simplify right side
   2,640.89x = 9,110,589.10
5. Step 5: Solve for x
   x = 9,110,589.10/2,640.89
6. Step 6: Final answer
   x = 3,449.81