Finding the Fourth Proportional to 2,626.72, 3,939.12 and 1,327.28

Step by Step Solution

1. Step 1: Write the proportion equation
   2,626.72 : 3,939.12 = 1,327.28 : x
2. Step 2: Convert to fraction form
   2,626.72/3,939.12 = 1,327.28/x
3. Step 3: Cross multiply
   2,626.72x = 3,939.12 × 1,327.28
4. Step 4: Simplify right side
   2,626.72x = 5,228,315.19
5. Step 5: Solve for x
   x = 5,228,315.19/2,626.72
6. Step 6: Final answer
   x = 1,990.43