Finding the Fourth Proportional to 2,389.24, 3,581.72 and 928.05

Step by Step Solution

1. Step 1: Write the proportion equation
   2,389.24 : 3,581.72 = 928.05 : x
2. Step 2: Convert to fraction form
   2,389.24/3,581.72 = 928.05/x
3. Step 3: Cross multiply
   2,389.24x = 3,581.72 × 928.05
4. Step 4: Simplify right side
   2,389.24x = 3,324,015.25
5. Step 5: Solve for x
   x = 3,324,015.25/2,389.24
6. Step 6: Final answer
   x = 1,391.24