Finding the Fourth Proportional to 1,320.56, 1,822.18 and 789.28

Step by Step Solution

1. Step 1: Write the proportion equation
   1,320.56 : 1,822.18 = 789.28 : x
2. Step 2: Convert to fraction form
   1,320.56/1,822.18 = 789.28/x
3. Step 3: Cross multiply
   1,320.56x = 1,822.18 × 789.28
4. Step 4: Simplify right side
   1,320.56x = 1,438,210.23
5. Step 5: Solve for x
   x = 1,438,210.23/1,320.56
6. Step 6: Final answer
   x = 1,089.09