Finding the Fourth Proportional to 2,638.38, 3,640.91 and 1,443.38

Step by Step Solution

1. Step 1: Write the proportion equation
   2,638.38 : 3,640.91 = 1,443.38 : x
2. Step 2: Convert to fraction form
   2,638.38/3,640.91 = 1,443.38/x
3. Step 3: Cross multiply
   2,638.38x = 3,640.91 × 1,443.38
4. Step 4: Simplify right side
   2,638.38x = 5,255,191.25
5. Step 5: Solve for x
   x = 5,255,191.25/2,638.38
6. Step 6: Final answer
   x = 1,991.83