Finding the Fourth Proportional to 1,438.64, 2,158.92 and 789.83

Step by Step Solution

1. Step 1: Write the proportion equation
   1,438.64 : 2,158.92 = 789.83 : x
2. Step 2: Convert to fraction form
   1,438.64/2,158.92 = 789.83/x
3. Step 3: Cross multiply
   1,438.64x = 2,158.92 × 789.83
4. Step 4: Simplify right side
   1,438.64x = 1,705,179.78
5. Step 5: Solve for x
   x = 1,705,179.78/1,438.64
6. Step 6: Final answer
   x = 1,185.27