Finding the Fourth Proportional to 2,133.89, 3,200.38 and 817.20

Step by Step Solution

1. Step 1: Write the proportion equation
   2,133.89 : 3,200.38 = 817.20 : x
2. Step 2: Convert to fraction form
   2,133.89/3,200.38 = 817.20/x
3. Step 3: Cross multiply
   2,133.89x = 3,200.38 × 817.20
4. Step 4: Simplify right side
   2,133.89x = 2,615,350.54
5. Step 5: Solve for x
   x = 2,615,350.54/2,133.89
6. Step 6: Final answer
   x = 1,225.63