Finding the Fourth Proportional to 2,638.15, 3,949.92 and 1,336.90

Step by Step Solution

1. Step 1: Write the proportion equation
   2,638.15 : 3,949.92 = 1,336.90 : x
2. Step 2: Convert to fraction form
   2,638.15/3,949.92 = 1,336.90/x
3. Step 3: Cross multiply
   2,638.15x = 3,949.92 × 1,336.90
4. Step 4: Simplify right side
   2,638.15x = 5,280,648.05
5. Step 5: Solve for x
   x = 5,280,648.05/2,638.15
6. Step 6: Final answer
   x = 2,001.65